Management of Finger Fracture Complications

7 Management of Finger Fracture Complications

Mick Kreulen

Abstract

Finger stiffness and pain, resulting in permanent impairment, and salvage procedures are the ultimate sequelae of finger fractures in dire straits. All due to a myriad of possible complications that may occur after trauma to the sophisticated and vulnerable anatomical harmony in the hand. The injury itself and all subsequent events, treatment as well as complications, will add to the risk of the dreaded permanent loss of finger function. It is simply because a lot more tissues than bone are involved in a fracture and its treatment. A finger fracture should therefore be regarded as a treacherous soft tissue injury around a small broken bone. In that way, the path of fracture treatment is paved in the service of soft tissue healing and restoring the biomechanical equilibrium of multiple tissues in close proximity.

A book chapter does not allow for a full appreciation of all possible finger fracture complications and their treatment. Especially the prevention, early diagnosis, and treatment of osteomyelitis and infection, deserve separate attention. The aim here is to advocate a systematic approach to all complications appreciating all involved tissues in phalangeal and metacarpal fractures in order to avoid the pitfalls of doing more harm than good. Three complications are discussed to illustrate this; nonunions, malunions, and, of course, the ultimate foe, finger stiffness.

Keywords: finger stiffness, malunion, nonunion, tendon adhesions, capsular contracture, ligament contracture, splint therapy, stepwise release surgery, osteotomy, bone reconstruction

7.1 Finger Stiffness

Joint stiffness is indeed the most common and notorious complication of a phalangeal fracture and can easily lead to a permanent functional impairment. The initial trauma, prolonged immobilization, surgery, but also overzealous therapy, all have a strong tendency to result in joint stiffness. Subsequent complications of whatever nature will increase this risk. Contractures in any position and stiffness in any direction is possible in all metacarpophalangeal (MCP) and interphalangeal (IP) joints. However, to maximize joint space in the swollen, injured hand, the MCP joints will tend to stiffen in extension and the IP joints in flexion.1^,²^,³ Joints do not have to be involved in the trauma to become stiff. The tendency toward stiffness expands to joints of uninjured fingers.⁴ Preventative measures should involve the entire hand, regardless of the injury.

The first causative agent in this tendency is edema from the inflammatory cascade. Edema itself is not a complication. The accumulation of edema is a natural response in the inflammation phase of any event within the layers of motion around tendons, ligaments, capsular structures, synovial spaces, and it acutely impairs joint motion. Edema control is one of the very first measures to take after a finger fracture. When edema continues or exacerbation occurs from interventions or early complications during the overlap with the fibroblastic phase of wound healing, the distended synovial spaces will transform with fibroblast proliferation. Adhesions and ligament shortening will effectively occur, promoted by collagen cross-linking.¹^,² Eventually, the changes become fixed and joint contractures will develop. As with infection and osteomyelitis, prevention is paramount:

●Edema control from the very start including elevation and compressive dressings.

●Infection prevention in open fractures and invasive procedures.

●Fracture treatment that allows for early PIP and MCP motion. This is actually a prerequisite for all surgical or nonsurgical treatment. From this perspective, stability of the fracture outweighs (but not eliminates) the discussion whether the position of the fracture is acceptable. An anatomical position of a fracture is only acceptable if it is stable enough to allow for stiffness prevention measures.

●In case of surgery, choose the least invasive fixation technique that is stable enough to allow for early protected motion. This is not automatically a plea for percutaneous K-wires as the best choice. If it fits the requirements, fine. But, all available techniques should be considered every time. Open reduction with screws, cerclage wires, or plates could very well be this “least invasive procedure.”

●Gentle tissue handling at all times. This also includes nonsurgical interventions.

●Immobilize as short as possible in the proper joint positions and provide removable splints for intermittent rest and protected motion during inflammatory healing phases.

●Unambiguously clear patient instructions. Prevent excessive active therapy during inflammatory healing phases.

The path of treatment for a finger fracture can either set the stage for an excellent outcome or provide a recipe for disaster.² Of course, the cascade toward stiffness cannot always be prevented. In high-energy traumas with serious soft tissue injury or in cases with fulminant complications like progressive osteomyelitis, the focus will divert to reducing the inevitable impairment. Proper alignment and functional joint positioning are secured to allow for residual dexterity or subsequent salvage procedures. Special consideration is needed for the presence of a complex regional pain syndrome (CRPS).⁵^,⁶ The treatment of CRPS is beyond the scope of this chapter, but the presence of painful dystrophic symptoms will definitely postpone or at least change the path of treatment as outlined here. CRPS will be discussed in Chapter 25.

7.1.1 Evaluation of the Stiff Finger

Joint stiffness after a finger fracture needs a systematic evaluation of all contributing factors. The pitfall here is the tendency of the patient, the doctor, and the hand therapist to first and only focus on the fracture and to treat the X-ray, rather than the patient. “If hand function does not return to normal, even after hand therapy, it must be because the fracture has not healed properly in an anatomic position and/or because any hardware is still in place that wasn’t there when everything was still okay.” And subsequently assume that a correction osteotomy or simple removal of hardware will automatically restore hand function to normal or expect this from a hand therapist. Of course, this might be true in a range of cases. But, to disregard complex finger biomechanics is to invite failure in a well-meant surgical attempt. A systematic and stepwise diagnostic approach is warranted and documented for each different type of tissue.1^,⁴^,⁶ Although it seems recommendable to avoid tunnel vision and start with physical examination before radiologic examination, it is better to be aware of hardware problems, a delayed or nonunion before manipulating the finger. The following six consecutive steps are the author’s preference to investigate a stiff finger as well as the adjacent uninjured fingers:

1.Needless to say, but often forgotten, is to first determine whether a preexisting stiffness was present before the injury. Any history of trauma, Dupuytren’s disease, musculoskeletal or neurologic disorders, rheumatoid disorders, gout or degenerative arthritis is first recorded. Of course, the nature of the trauma combined with the treatment path so far will be the first direction indicator for the causes of stiffness.

2.Next is an X-ray examination in three directions. A posteroanterior, a lateral, and an oblique view to assess delayed or nonunion, the presence and position of implants, osteomyelitis, callus formation, degenerative arthritis, joint incongruity, and any other malunion or exostoses. These may all disturb the biomechanical equilibrium of the musculoskeletal system, add to stiffness, and cause pain and/or a structural motion blockage. A CT-scan can help in mapping joint surface incongruity as will be discussed in the paragraph on malunions.

3.Inspection and observation of the entire hand can be very informative. The aspect of the hand can show signs of infection, residual edema, scars, dystrophic symptoms, and the deformity at rest. Finger motion is observed during the attempts of different functional grips. Some deformities concomitant to stiffness and pointing to contributing factors will only become apparent in motion. For example, the “loss” of a knuckle or scissoring of fingers during flexion, and a swan neck deformity or finger deviation during extension. Paradoxical DIP-extension as the patient pulls the FDP tendon at end-range flexion may indicate the contribution of lumbrical tightness which, in isolation, can only be found by observation. However, limited joint flexion, interosseous muscle tightness, or adherence of the flexor tendons within zones 1 or 2 can prevent demonstration of lumbrical muscle tightness.

4.Palpation and manipulation of the finger for residual edema, skin turgor, scar contractures, subcutaneous fibrosis, hardware prominence, flexor bowstringing, etc. Painful neuromas, hypersensitive skin, and disturbed soft tissue vascularization are also detected by touch and could also contribute in the cascade toward stiffness and/or will at least affect any treatment regime. The location of the fracture and adjacent joints are palpated and tested for clinical instability or rigidity. If joints are very stiff or fixed in a contracture, distinction between musculotendinous, ligamentous, and capsular contributions is not possible on physical examination and might probably be all involved.⁵ In such cases, the next step is impossible to perform and can be skipped.

5.Still holding the hand, joint motion is tested relative to the position of adjacent joints. Is the limitation of joint movement fixed, or does it vary with the position of other joints? First, the intrinsic tightness test where PIP joint flexion is affected by the position of the MCP joint. A decreased passive PIP flexion with the MCP joint held in extension as compared to the MCP held in flexion and to uninjured fingers indicates involvement of the intrinsic muscles. As said, this test might be impossible to perform in the presence of structural ligamentous contractures, adhesions, malunions, or pain. If applicable, it should be documented that intrinsic muscle tightness is not excluded yet and be examined at a later stage. Intrinsic muscle involvement is too often overlooked. Second, the Oblique Retinacular Ligament (ORL) tightness test is performed (Landsmeer test). If passive extension of the PIP joint brings the DIP joint in full and stiff extension and when DIP flexion is only possible with the PIP joint in flexion, this is suggestive for ORL tightness. A contracture that might develop in pseudoboutonniere deformities, for example after dorsal angular malunions of the proximal phalanx. The third relative motion test is for extrinsic tightness, when IP-joint flexion decreases with MCP and wrist flexion, suggestive for extrinsic extensor muscle contracture.¹^,³^,⁵ Likewise, extrinsic flexor muscle contracture is suspected when IP-joint extension decreases with MCP and wrist extension.

6.Measurement of passive versus active range of motion of all finger joints of the affected hand. Extrinsic extensor- or flexor tendon adhesions are most likely the predominant contributors if passive motion exceeds active motion.¹^,³^,⁶ However, a discrepancy in passive and active extension could as well be caused by tendon disruption,⁶ a shortening malunion or angulation in the sagittal plane found in step 2. Again, joints can be completely stiff with an equally limited passive and active motion in any position of the adjacent joints.

In all cases, a systematic examination and documentation will always provide necessary information for any treatment plan, also in the presence of an obvious and predominant malunion, nonunion or in the presence of a completely fixed joint that does not respond to any provocative testing. Additional radiologic examination might help. The development of sophisticated ultrasound probes and high-resolution 3T-MRI with dedicated coils are capable of an increasingly meticulous scrutiny of the injured tissues but also require increased understanding of the radiologist on local anatomy and pathofysiology.7 In general, it is best to proceed with a nonsurgical treatment protocol based on the findings of examination. Besides a high chance of improvement, it serves a diagnostic purpose because different elements of stiffness are revealed only as others are resolved.¹ Treatment of the stiff finger is also a stepwise process with repeated examination after every improvement.

7.1.2 Treatment of the Stiff Finger

Nonoperative Therapy

As a general rule, nonoperative therapy precedes surgical intervention.¹^,³ It serves more purposes than just the attempt to resolve finger stiffness. As stated above, it might have a diagnostic value. For example: the extent of a rotation malunion and its effect on functional grips will only become apparent when finger flexion increases, any intrinsic tightness will only become apparent when capsular contractures resolve, and the distinction between capsular tightness and tendon adhesions can only be made when passive motion increases. Furthermore, a hand therapist will invest in patient education, shared decision making and setting realistic functional goals tailored to the patient’s needs. The educated patient is a strong ally² and a clear motivation is paramount to embark on a journey stretching over many months of rehabilitation and possible surgical interventions.⁵

The basis of nonoperative therapy to resolve finger stiffness is to put a low-load prolonged stress on the contracted soft tissues in order to gain plastic deformation in the desired direction.¹^,³ Both static and dynamic splinting regimes have proven to be quite successful in resolving fingers stiffness.²^,⁴^,⁵^,⁶ Proper splinting is adjusted to the desired direction of plastic deformation, the support of any instability, the amount of allowed protected motion, the control of edema, and the relaxation needed to relieve inflammatory signs. A skilled hand therapist will be able to compose the right splinting regime for each individual stiff finger:

●Serial casting.

●Static-progressive splinting.

●Dynamic splinting.

●Relative motion splinting.

Serial casting and static-progressive splinting are gaining preference as the first choice. Plastic deformation of the contracted tissues appears to be best achieved by a stress-relaxation method and, especially in serial casting (Fig. 7‑1a), this method is less prone to overzealous exercising and the dreaded exacerbation of inflammation. Inflammatory signs will need a regime that allows for periods of relaxation. Both in static-progressive splinting and serial casting the joint is held at a constant position without continuous pull. The amount of force required to maintain that position decreases with time, as the tissue stretches by plastic deformation, until an equilibrium is reached and the cast can be adjusted or replaced.¹^,² A static-progressive splinting regime (Fig. 7‑1b) also works according to the stress-relaxation method but in contrast to serial casting, the splint can be made adjustable and removable to allow for motion exercises.⁴^,⁵

Fig. 7.1 Examples of the four different splinting principles for a proximal interphalangeal (PIP) flexion contracture of the middle finger. (I acknowledge the input of the hand therapists of the Amsterdam Hand & Wrist Centre, HPCA, for these photographs.) (a) An example of serial casting. (b) An example of a static-progressive splint. (c) A dynamic traction device. (d) A relative motion splint to enforce active PIP extension.

Dynamic splinting with some kind of continuous traction device (Fig. 7‑1c) is preferred in later and persistent stages of stiffness, after the inflammatory cascade has subsided and when motion exercises are necessary to preserve residual gliding qualities of soft tissues. The greatest risk of a dynamic regime is to put too much force on the tissues.³^,⁴ Overzealous redression and forceful exercise by either a hastily patient or an inexperienced therapist will do more harm than good. On the other hand, a properly adjusted continuous traction device and well-educated exercises may offer a beneficial regime for both gliding surfaces and tissue contractures. Plastic deformation of the contracted tissues in dynamic splinting is achieved by creep. Creep is the deformation of tissues while placed under constant traction-stress for an extended period of time.²

A well-known but not often applied splinting technique for PIP or even DIP joint stiffness is the relative motion splint (Fig. 7‑1d). The technique is widely accepted to aid in the recovery of tendon repair and boutonniere deformities. It allows immediate active motion relative to adjacent fingers with tendons from a shared muscle.⁸ The same splint might also enforce active PIP extension or flexion by restricting the MCP joint. In other words, the force for extension or flexion is diverted to the PIP joint because it cannot be taken up by the hypermobile MCP joint.⁹ This might be of beneficial aid to active motion exercises. Especially intrinsic tightness, muscle contractures, or tendon adhesions can be directly addressed with the relative motion method. In summary, seven principles of nonoperative therapy can be distracted from this paragraph:

1.Patient education.

2.Edema control.

3.Assessment of inflammatory signs.

4.Proper splinting regime.

5.Active and passive motion exercises of all fingers.

6.Measuring progress and repeated examination of the contributing factors to residual stiffness.

7.Supporting the patient to resume daily activities and return to work.

Surgical Treatment of the Stiff Finger

Nonoperative therapy should continue as long as there is improvement, even if it is only a slight or slow progress.3 The treatment regime is only reconsidered if an objective plateau has been reached and several weeks or even months pass with no further resolution of stiffness.¹^,²^,⁵^,⁶ Surgery is not an alternative to nonoperative therapy or vice versa. Both treatments should facilitate each other to achieve the optimal result. At some point, surgery might be needed for nonoperative therapy to proceed and vice versa. For example, a malunion might need to be corrected first before therapy can be resumed, or therapy is needed first to resolve capsular stiffness before surgical tenolysis or tendon reconstruction can be successful. Again, a stepwise and systematic approach is warranted. This paragraph will focus on this approach rather than outlining details of surgical techniques. As said, the first step is to repeat full examination of the stiff finger and to make an inventory of contributing factors to the persistent stiffness. Next is to determine the timing and sequence of interventions. In the ideal timing for surgery:

●The inflammatory phase has subsided.

●There is no longer fluctuating edema.

●Therapy has reached a plateau in positive progress.

●Scars are fully matured.

Any divergence from this ideal timing needs appreciation of the risk of associated complications weighed against the need for earlier surgery. Of course, complications like the presence of active infections, paronychia, panaritium, osteomyelitis, or purulent arthritis will immediately bypass any timing criterium for surgery in a stiff finger. These need acute treatment. But also, failed, insufficient, prominent, or broken hardware are examples that might need earlier surgery. Painful neuromas or foreign bodies can seriously impede therapy and also warrant earlier surgery. In those cases, a single and least invasive procedure is chosen that fully resolves the problem at hand. Any further elective procedures on the inventory list should wait until the timing criteria above are met.

As a rule of thumb, one surgical session should only combine multiple procedures that can be performed through a single approach (dorsal, volar, or lateral) and that do not require conflicting postoperative therapy. Combining multiple approaches in one surgical session should be avoided.2 The risk of creating more complications and disappointing results increases exponentially with the extentf of surgery.⁴ Moreover, it is false to assume that the same result can be achieved in a reduced rehabilitation time when all contributing factors are surgically treated in one session. Stepwise and well-timed multiple surgical sessions are aimed to facilitate nonoperative therapy in a continued resolving of stiffness that might even reduce the need for further surgery.⁶ On the other hand, all procedures that can be combined in one session through the same approach should be combined. Intraoperative stepwise surgery in one session is possible with a wide awake patient under local anesthesia. It enables to determine the progress from each procedure and the need to proceed with subsequent procedures in the same session.²^,³^,⁵^,⁶ From this perspective, surgical procedures that might be necessary can be grouped into three categories of possible combinations:

1.Bone and skin reconstruction. Primary surgical attention should be directed toward problems with skin and bone. Malunions, nonunions, exostoses, or malposition of implants are addressed in the first surgical step.⁶ The paragraphs on malunion and nonunion will elaborate on this. Also, bone reconstruction needs a well-vascularized soft tissue coverage. Scar contractures and soft tissue coverage of questionable quality are preferably reconstructed at the same time. Bone reconstruction should not be combined with extensive release procedures beyond the approach for the skin and bone procedure or with tendon reconstructions. The goal here is to achieve functional and stable anatomy of the joints, phalanges, and/or metacarpals with well-vascularized soft tissue coverage to allow for optimal resumption of nonoperative therapy.

2.Release procedures and hardware removal. When nonoperative therapy is no longer able to further improve stiffness and bone and skin have healed properly, the focus will be on persistent capsular and ligament contractures, muscle contractures, and tendon adhesions. Ideally, a single approach is selected for a stepwise release of all adhesions and contracted structures under local anesthesia. For example, the preferred midlateral approach dorsal to the neurovascular bundle might allow for dorsal and palmar exposure of all structures that need release in a PIP flexion contracture.³^,⁵^,⁶ However, the concomitant need for flexor tendon tenolysis or a pulley reconstruction will prefer a palmar approach.⁵ Previous surgery, hardware location, or a full extensorhood release may prefer a dorsal approach. Multiple approaches should not be combined in one session and the need for extensive release procedures on both the dorsal and palmar aspect of the digit will require a staged surgical treatment.²^,⁶ Regardless of the approach and techniques, less than full range of motion should be anticipated following multiple necessary surgical release procedures.³ When a two-staged release in this category is planned, the ratio to first address either the dorsal or palmar side depends on the functional desire of the patient and the position and extent of the contractures. In general, it is preferred to first improve lost flexion of the MCP and PIP joints.² Any hardware on the dorsal or lateral aspect is removed. From proximal to distal and only if needed, a stepwise consecutive release of zone 5 and 6 extensor tendon and sagittal band adhesions, the dorsal capsule of the MCP joint, the entire extensorhood and the intrinsics, the dorsal capsule of the PIP joint, the oblique retinacular ligament, further distal extensor tenolysis, or even Fowler’s tenotomy are all combined at this stage.²^,⁵^,⁶ The goal here is to at least restore passive MCP, PIP, and DIP flexion and facilitate active extension to the point of maximal passive extension. In a later stage, palmar release procedures will address residual PIP and DIP flexion contractures.² A palmar Bruner’s or midlateral approach under local anesthesia is used to consecutively release zone 1 and 2 flexor tendon adhesions, the transverse retinacular ligament, the accessory collateral and checkrein ligaments, and, if still needed, a resection of the proximal volar plate. Although release procedures are preferably not combined with reconstructions, an exception is made for a pulley reconstruction. A skilled therapist will be able to protect a reconstructed pulley while exercising tendon excursion. Successful release procedures are aimed to achieve both passive extension and flexion to the level of functional desire. Postoperative therapy is started immediately after surgery and will focus on edema control, maintaining the gained passive motion and exercising active flexion and extension. In the majority of cases, no further surgery will be necessary. Silastic rods are implanted in this step in the exceptional case that needs a staged flexor tendon reconstruction.

3.A final and last category is reserved for tendon reconstructions. Tendon reconstructions or transpositions require optimal results of all previous steps: bone and joint stability, a well-vascularized gliding soft tissue environment, and a full passive motion in the desired functional range. Either flexor digitorum profundus reconstruction or extensor tendon reconstruction at the level of the PIP joint is most common at this stage.

When multiple surgical steps are necessary, it is important to start the next step only if the timing criteria have been met again. Needless to repeat, the entire treatment is a long process that requires a close threefold collaboration of hand surgeon, hand therapist, and patient. After each step, whether it is surgical or nonsurgical, gained results are shared as a team and new goals are set for the next step. A motivated and diligent team with realistic goals will be able to achieve the maximal functional result in the challenge to overcome a stiff finger. However, at any point in this trajectory an acceptance and coping with residual stiffness should also be considered and weighed against a realistic improvement from continued treatment. The next two paragraphs will illustrate that also salvage procedures should be considered in seriously injured fingers. Against wishful judgment, an arthrodesis or even amputation can be the best option in severe cases.

7.2 Malunion

A malunion is generally defined as an incomplete bone union or union in a faulty position. Its definition does not include a minimum degree of incompleteness or faulty position. It also does not include any relationship to functional impairment or long-term degenerative risks. As clinical hand surgeons, we have a natural tendency to use the term “malunion” as a diagnosis instead of a symptom. It is not a diagnosis. It is an objective finding that might have a cause-and-effect relationship with a functional deficit. There are three additional pitfalls in looking at malunions of phalangeal and metacarpal fractures:

1.A malunion is commonly described in a single plane. Similar to fracture dislocations as an angulation-, translocation-, shortening-, or rotational deformity. Each referring to a dislocation in only one plane. Most often in the sagittal (volar versus dorsal) or coronal (lateral) planes. While in reality, it should always be considered as a three-dimensional deformity in multiple planes. We tend to use its most prominent deformity in its most obvious plane for characterization of the malunion. For example, “a rotational deformity” or “a dorsal angulation malunion.” It should be noticed that a rotational deformity probably also has a component of shortening and angulation, and a dorsal angulation malunion will also angulate in the coronal plane and could have a component of rotation and translocation. When planning a reconstructive procedure, all planes of malunion and their contribution to the functional deficit should be recognized.

2.It is difficult to get a reliable measure of the actual extent of the malunion on standard radiographs. Again, it should be remembered that we are looking at a two-dimensional representation of a three-dimensional problem. The slightest difference in view will affect the angle of the dislocation, the amount of shortening, the widening of the gap. Keep this in mind when you compare your measurements to reference values in the literature. It is important to realize that measurements on standard radiographs are mere indications of the degree of malunion in only one plane, and also as only one part of the analysis of the patient’s complaints and functional deficit. A 3D CT-scan will help in cases where a reliable measurement of the malunion in multiple planes is needed.

3.It can be difficult to predict functional deficit from a malunion. Is the malunion the main (and only) accountable source of the functional deficit? And to what extent? We are often provided with maximum acceptable degrees of angulation, maximum millimeters of shortening, or a maximum percentage of joint surface involvement. Our stock of knowledge includes well-supported data from biomechanical and anatomical research or widely accepted expert opinions. From this base, it is tempting to jump to a fast conclusion putting a cause-and-effect relationship between an objective malunion and an objective functional deficit. And subsequently, to expect that surgical correction of only that malunion should be able to correct the functional deficit in full. This pitfall carries the risk of inviting failure to your procedure. Even if we are confident in our measurements and the deformity is significant, we should be aware that the malunion is not necessarily the only causative agent of the functional deficit of the affected ray. There are always exceptions to this rule. For example, it is safe to fully attribute finger scissoring to an objective isolated rotational deformity in the presence of a painless full range of motion. In the paragraph on finger stiffness, the quality and integrity of all soft tissues in the zone of injury are addressed as important possible contributors to complaints and functional deficits after phalangeal and metacarpal fractures.

7.2.1 Treatment of Malunions

Surgical correction of a malunion is indicated when a realistic expectation of satisfactory relief of symptoms outweighs the investment of a surgical procedure, the risk of new complications and the time needed for healing and rehabilitation. It can be only the first step in resolving finger stiffness as explained in the previous paragraph. From this perspective, the surgical plan should be aimed at a functional gain tailored to the needs of each specific patient. On the other hand, not all malunions cause a disabling functional deficit. A slight malunion might only present as an apparent loss of a knuckle, a minimal change in alignment of the finger, a minimal rotation of the nail, or only a slight loss in range of motion. All without the loss of functional ability. Intact functional grips of the hand might feel unusual to the patient without actual impairment. The patient’s desire for surgical correction of a minor malunion is sometimes only based on frustration about a nonanatomical healing of the fracture and a changed appearance of the hand as compared to the other hand, without any functional deficit. It should be discussed whether the combination of a correction osteotomy with (secondary) multiple release procedures to gain those last 20 degrees of motion is realistic and worth the risk of new complications. On the other hand, the aesthetically displeasing loss of the knuckle in a volar angulation malunion of the fifth metacarpal neck with maybe a slight loss of finger extension might not pose any functional limit to hand function, but still worthwhile to consider surgical correction in a well-informed and motivated patient. Of course, these considerations should have been taken into account in the acute stage of fracture treatment when a certain degree of dislocation was accepted to heal in malunion, especially in metacarpal neck fractures.

The first step before making a surgical treatment plan is to resolve any concurrent joint stiffness as much as possible by an optimal nonoperative therapy regime as outlined above. Ideally, edema and inflammation should have subsided, soft tissues should be healed, and any fibrotic scarring matured. As with the stiff finger, the hand therapist plays a valuable role in this process and helps to determine the functional goals tailored to the patient’s needs. The surgical malunion correction plan should include the following:

●Infection prevention.

●The approach, site, and type of correction osteotomy.

●The possible need of a cancellous or structural bone graft.

●The choice of implant.

●Adjunct soft tissue procedures.

●Postoperative rehabilitation regime.

Metacarpal Malunions

The most common malunions of metacarpal neck fractures are volar angulated due to the pull of the intrinsic muscles. The angle that can be tolerated increases toward the fifth ray. As said, exact tolerable angles can be treacherous to use, vary considerably, and do not address the needs and desire of the patient. That said, the reported tolerable angles range from 10 degrees in the index and middle finger 10^,¹¹ increasing to a tolerable angle in the little finger beyond the commonly assumed 30 degrees¹² up to a maximum of 70 degrees.¹³ Take into account that angulation is often combined with a less prominent rotation deformity and shortening. In general, correction osteotomy is best performed at (or very close to) the site of the old fracture where normal anatomy can be restored and multiple planes of malunion can be corrected. A closing wedge osteotomy is easier than an opening wedge osteotomy but shortens the metacarpal further. An opening wedge osteotomy is preferred in cases with a surgical goal to correct an extension lag combined with a significant loss of power. A stable fixation (plate & screws) will be needed to allow for early mobilization.¹⁴

The second common metacarpal malunion is a dominant rotational deformity after oblique or spiraled metacarpal shaft fractures. Because of its distance to the finger-tip crossing three joints, only a slight metacarpal rotation error can result in disabling scissoring of the fingers during functional grips. The immobilization period of metacarpal fractures has shortened considerably in the last decades and early finger movement is encouraged. This has resulted in the possibility of an early detection of a developing rotation malunion. Because full osseous union will not be complete in the first months, it might still be possible to open the original plane of the fracture and restore normal anatomy. This is an additional argument for planning the osteotomy at the site of the malunion. Alternative classic sites of osteotomy are described proximal to the malunion at the metacarpal base as a transverse or step-cut osteotomy. These can be considered in cases with a full osseous union, without other planes of malunion to correct, without adhesions to release and with a limited need of derotation or in cases where the malunion site has questionable bone stock or soft tissue coverage. However, a clinically significant rotational deformity is typically a malunion to correct early at the site of the deformity, either opening the original plane or with a derotational osteotomy and a stable fixation to allow for early mobilization.

Phalangeal Malunions

Treatment of phalangeal malunions is far more challenging. The proximal phalanx is encapsulated in the ingenious intrinsic and extrinsic assembly of tendons with a high tendency for malunion in unstable fractures, tendon adhesions, and the development of PIP and DIP contractures. Typical dorsal angulation of fractures in the base of the proximal phalanx can be insidious to assess on standard radiographs. The proximal fragment of base and shaft fractures is flexed by intrinsic muscle force while the dorsal fragment is extended. The dorsal surface of the phalanx shortens relative to the length of the extensor apparatus, creating a biomechanical dysbalance and a pseudoboutonnière deformity. If left untreated, a staged and stepwise approach is necessary as outlined in the paragraph on the stiff finger. In general, a closing wedge osteotomy and a lateral plate at the site of the original fracture is preferred.¹⁰ This might be challenging due to its proximity to the PIP or MCP joint, the close relation to the extensor assembly and the desire to fit a stable fixation. Some divergence from the old fracture site might be necessary to avoid further complications. Dorsal plating is second best and should be avoided in the distal half of the proximal phalanx, closer to the PIP joint. It interferes with the extensor assembly and a later plate removal and tenolysis should be anticipated. However, the proximal phalanx base close to the MCP joint in the middle and ring finger will often require dorsal plating or alternatively, a crossed K-wire fixation. Opening wedge osteotomy with a bone graft also carries the risk of new adhesions and contractures with a high chance of subsequent tenolysis and/or capsulolysis.¹⁵ These are reserved for the need to correct significant phalangeal shortening or malunions in the coronal plane.

The relation of the middle phalanx to the extensor assembly does allow for small dorsal plating at its base or small well-fitted lateral plating at its shaft or distal half. But, crossed K-wire fixation with good bone contact that allows for early mobilization is generally preferred in the middle phalanx.

Intra-articular Malunions

In addition to malalignment in multiple planes and all aforementioned issues to consider, an intra-articular incongruity and chondral injury may further complicate the malunion with pain, arthritis, and the risk of progressive degeneration. A developing intra-articular malunion is therefore best corrected early. Ideally, the old fracture line is opened to restore normal anatomy. However, this should only be performed in the presence of large fragments. The risk of creating multiple small fragments with questionable viability without the possibility of a stable fixation should be avoided to prevent nonunion, osteonecrosis or fixation failures. Therefore, the first step is to evaluate the size and course of the original fragments and the quality of the joint surfaces. A 3D CT scan is often necessary for proper assessment. Combined with patient characteristics and functional desire the following four options are considered:

1.Early osteotomy within the first months when osseous union is not yet complete. This creates the advantage of restoring normal anatomy but is only reliable in the presence of one or two large viable fragments. The case in Fig. 7‑2 is a 16-year-old female, 10 weeks after trauma. The fracture site of the large fragment could be opened and intra-articular anatomy restored.

2.Advancement osteotomy¹⁶ is a smart technique that enables to focus on joint congruity and malunion correction but ignores the old fracture lines. Osseous union should be complete because osteotomy is planned at the site of the original fracture, but not in the fracture itself. It is described for malunited condylar fractures but can also be applied in other intra-articular malunions. Preferably, one new large fragment is created at the site of the old fracture and advanced to correct the malunion and restore the joint surface (Fig. 7‑3). Some challenging creativity is sometimes needed to plan the osteotomy keeping three goals in mind: (1) restoring joint congruity, (2) restoring phalangeal alignment in all planes, and (3) creating one or two new large viable fragments that allow for stable screw fixation.

3.Accept the articular incongruity and instead perform an extra-articular osteotomy to correct the angular and/or rotational deformity produced by the malunion.¹⁰^,¹⁴ Although this technique might feel suboptimal, it eliminates the risk of further intra-articular complications and restores proper alignment for the residual range of motion. This is especially suitable for patients with malaligned fingers without pain, with an acceptable range of motion and with multiple small intra-articular malunited fractures in the more forgiving MCP and DIP joints.

4.While beyond the scope of this chapter, reconstruction or salvage should always be on the list of options.³ For example, the experience with a Hemi-Hamate arthroplasty for a partially destroyed volar base of the middle phalanx has optimized this technique to yield a reliable option for these intra-articular malunions. Smaller defects might be salvaged by a volar plate advancement arthroplasty. Larger chondral defects in stiff, painful joints might not benefit from osteotomies or reconstruction and are best treated with arthrodesis or a prosthetic arthroplasty. Typically, in painful and destructed DIP-joints, thumb and index PIP finger joints, an arthrodesis is the first choice, and in all other MCP and PIP joints a prosthetic arthroplasty is the first choice. This depends, of course, on the complaints and functional desire of the patient.

Fig. 7.2 (a) A 16-year-old female complained of pain and angulation of the fourth finger after nonsurgical treatment of an accepted dislocation in an intra-articular proximal interphalangeal (PIP) fracture in her left nondominant hand. (b) Computed tomography (CT) scan image of the finger shows a malunion of a proximally dislocated monocondylar fracture with an intra-articular step-off and angulation in the PIP joint. (c) The intraoperative view, 10 weeks after trauma, still reveals an intra-articular gap and a rotation of the proximally displaced ulnar condyle. The original fracture-site could be used for osteotomy. (d) Advancement and derotation of the large viable fragment and screw fixation. (e) Original intra-articular anatomy is restored. (f) Complete union and malunion correction is achieved. (g) Postoperative active extension of the finger. (h) Postoperative active flexion of the finger.