27 Other Carpal Fractures Abstract Fractures of the carpals, which do not affect the scaphoid, are less common fractures. The most common is the dorsal chip fracture of the triquetrum, which can usually be treated conservatively. In carpal body fractures, on one hand, the possibility of a complex injury with carpal instability is to be considered, on the other hand, the exact restoration of height and joint surfaces is required to avoid carpal malalignment and secondary osteoarthritis. When diagnosing, it should be noted that the fractures are often difficult to detect on the plain X-rays. At the slightest suspicion, therefore, a CT-scan should be made, which usually shows the diagnosis clearly. This is the only way to ensure timely treatment, which can safely avoid the long-term consequences of overlooked fractures, which often cannot be corrected later. Keywords: carpal fracture, trapezium, triquetrum, pisiform, Lunate, hamate, treatment options, making diagnosis In the region of the carpus, the scaphoid fracture is the most common fracture by far. Their frequency is given according to literature with up to 60 to 85%.1,2 In this light, the fractures of the other carpal bones seem to play only a minor role, since its frequency is only about 20% of carpal fractures in the literature. Considering that this number is distributed even on the remaining seven carpal bones, we find for the other carpal bones even only frequency rates in the single-digit range, sometimes by 1% or less depending on which carpal bones it is calculated and which literature is cited ( Regarding the trauma mechanism, the most common mechanism is certainly the fall on the hand. However, in rare cases of carpal fractures, bruising and axial forces can lead to individual trauma. Open fractures in complex hand injuries can cause unusual fracture patterns ( Fig. 27.1 Carpal bones. (This illustration is provided courtesy of Dr. Nasa Fujihara.) With regard to the diagnosis, it can generally be said that localized pain and swelling follow the anatomical localization of the affected carpal. Corresponding anatomical knowledge of the landmarks of the carpus are required here. The X-ray image of the wrist in two planes, possibly with oblique views, is certainly the basic diagnosics for the carpal fractures. In all unclear or confusing situations, the application of computed tomography (CT) scan should be generous, as in the simple X-ray images, just in the area of the carpus and carpometacarpal (CMC) joints, overlappings often occur which do not clearly indicate fractures. Also, wrist arthroscopy can be helpful in making or confirming the diagnosis and can be used as assistance for closed reduction and fixation (see also Chapter 8). With regard to the treatment of other carpal fractures, it can generally be said that reduction and fixation in dislocated fractures is usually either closed or open. As osteosynthesis material are primarily Kirschner’s wires, mini screws or headless screws of the Herbert screw type used. For nondislocated fractures or undisplaced bony avulsions, conservative treatment is also possible. This conservative treatment usually consists in a 4-week immobilization of the wrists, leaving the finger joints and the thumb free. The triquetral fracture is the most common carpal fracture after the scaphoid fracture with a range of 3 to 5% of carpal fractures. The most common trauma mechanism is the fall on the extended hand and wrist. Hyperflexion is also blamed for some avulsions at the dorsal side of triquetrum. In the dorsal, cortical chip fracture of the triquetrum, the ulnar styloid shall act as a chisel to shear off the dorsal, cortical surface in hyperextension and ulnar inclination of the wrist.4 Triquetrum fractures are classified generally in three different types. The majority of fractures is the small cortical fracture on the dorsal aspect of the triquetrum which is with 93% the most frequent triquetrum fracture.4 The second type is the body fracture of the triquetrum. Body fractures can be classified by the course of the fracture line in the sagittal or horizontal or oblique plane. The rarest condition is the palmar avulsion fracture which is probably a bony avulsion of the strong palmar lunotriquetral (LT) ligament. In triquetrum fractures, the pain is typically located over the dorsal ulnar aspect of the wrist. Using the landmarks of pisiform bone and ulnar styloid, it is easy to locate the precise spot of the triquetrum. Fig. 27.3 (a) Dorsal chip fractures of the triquetrum are usually not visible on AP view, (b) but they are easy to detect on lateral X-rays of the wrist. (c) Body fractures are also visible on AP view. Basic imaging is X-ray of the wrist in anteroposterior (AP) and true lateral view. X-rays in AP view are often not helpful because the most frequent dorsal cortical fracture is usually hidden behind the bony structure of the carpal bones. For the easy dorsal cortical fracture, true lateral X-ray is usually sufficient to make definitely the diagnosis of this fracture ( Dorsal cortical fractures usually show no additional lesions. When diagnosing a body fracture, one should be aware of an additional fracture in the carpus or a malalignment due to a greater arc injury with carpal instability. No randomized controlled studies exist. The majority of the triquetrum fractures are the dorsal cortical chip fractures and nondisplaced body fracture. I usually treat the dorsal chip fractures conservatively with a forearm splint or cast. It should not include metacarpophalangeal (MCP) joints and the thumb, so that early active motion of the fingers is possible. For chip fractures, the period of immobilization is 3 weeks. After the immobilization, there will be a longer period with tenderness in the area of the chip fracture. Sometimes, for some weeks there is no bony union of the chip fragment. Sometimes, it remains a nonunion, but usually pain and tenderness disappears after 3 to 6 months. If pain persists over 6 months or longer, treatment of choice is the excision of the pseudarthrotic fragment. However, this is really a rare condition. Only very large dorsal fragments can be fixed with a small screw if they have a significant amount of join surface. In nondisplaced body fracture, I immobilize the wrist for 4 weeks in the same type of splint or cast. Afterward mobilization of the wrist begins with loading of the wrist only 2 months after injury. The wrist can be loaded gradually to full activity after 3 months. In displaced body fractures, I treat with open reduction and internal fixation to ensure that the joint surfaces are really congruent. The material for fixation depends on the type of fracture. In these rare conditions, I have used wires, and small headless compression screws and mini screws ( Concerning the small fragments some, authors recommend 4 weeks immobilization. Dislocated body fractures of the triquetrum can also be reduced in a closed manner with percutaneous fixation. For the internal fixation in open reductions also mini plates and staples can be used. The prognosis of the cortical dorsal chip fractures is good. Höcker and Menschik5 published a series of 65 patients where conservative treatment with immobilization for 3 weeks was successful after a mean period of 47 months. For the body fractures, due to the small number of cases, exist no reliable data. If joined surface is restored smoothly, prognosis will be good as well. In fracture dislocations of the carpus, prognosis is determinated less by the fracture then by the carpal ligament injury. Pisiform fractures are rare fractures with a frequency of about 2% of carpal fractures. Most of them caused by a direct blow or a fall on the outstretched hand.6 The pisiform is a special carpal bone because it is the only one which is not integrated in the carpus and actually a sesamoid bone of the flexor carpi ulnaris (FCU) tendon. So, fracture can occur either due to direct force to the bone or due to traction of the FCU tendon while the pisiform bone is compressed against the triquetrum during the fall on the outstretched hand. Four different types of pisiform fractures were distinguished. First is the transverse fracture of the pisiform; second is the parasagittal fracture line; third is the comminuted fracture; and the 4th is the impression fracture of the pisiform into the triquetrum. The pisiform bone can easily be palpated on the palmar surface of the wrist close to the ulnar side of the distal flexion crease of the wrist and in the course of the FCU tendon. Pressure on the palmar surface leads to pain. Also pushing the pisiform from ulnar to radial while shifting it over the triquetrum courses usually pain. Standard X-ray of the wrist in two planes are usually not appropriate to detect the pisiform fracture. The typical clinic in pain should directly trigger the special view 40 degrees supination compared to the true lateral view ( Potentially, there can be a rupture of the FCU tendon, but this is really a rare condition. There are only about 200 pisiform fractures, which are published in the literature, so we cannot find reliable evidence. In nondisplaced fracture, I treat with a forearm cast with free MCP joints and thumb for 4 weeks. After removal of the cast and X-ray, control gradually loading is usually possible even if there is some tenderness projection of the passive form during the following weeks. In these cases, physiotherapy is usually not required. In displaced fractures, and fractures with comminution of the joint surface, I excise the pisiform. I use an angular incision over the palmar aspect of the pisiform. After neurolysis and protection of the ulnar nerve, the FCU tendon is longitudinally split and the pisiform is removed in the subperiosteal layer. The longitudinal split of FCU tendon is sutured with an absorbable running suture. The wrist is immobilized for 3 weeks. In nondisplaced fracture, there is no alternative to immobilization of the wrist. In simple fractures, open reduction end fixation of bone could be an option. The results after conservative treatment end usually in bony union and are usually good. In cases of pisiform excision, Carroll and Coyle7 reported about good outcome with free function regarding the FCU tendon as well. Lunate fractures are really a very rare condition and are responsible for not more than 1% of the carpal fractures.8 If we see a fracture of the lunate, we should always be aware that most of the fractures of the lunate are caused by the Kienböck’s disease ( According to Teisen and Hjarbaek,8 there exists a classification of five types of lunate fractures: Type I: palmar pole fracture Type II: osteochondral chip fracture Type III: dorsal pole fracture Type IV: sagittal fracture Type V: transverse fracture Pain over the the middle part of the wrist especially on the dorsal side with increase while moving or loading. Standard X-rays of the wrist in AP and true lateral view are the basic instruments of diagnosis. If there is suspicion of lunate fracture, CT scan and magnetic resonance imaging (MRI) should both be performed to rule out a Kienböck disease or carpal instability.
27.1 General Considerations
Fig. 27.1). It should be noted, however, that it is precisely the rare occurrence of a fracture that often leads to uncertainty in the treatment, as in the daily routine not always immediately available knowledge of comparable cases is available to the hand surgeon. Also in this respect, it is interesting to deal with these fractures.
Fig. 27.2). Basically, three types of carpal fractures can be distinguished from the severity of the acting force. In the case of very severe trauma forces, dislocation fractures can occur which, in addition to the fracture, also lead to instability in the area of the carpus and are therefore originally classified as carpal instabilities. Typical are the perilunate fracture dislocations, which not necessarily have to affect the scaphoid, as in De Quervain’s dislocation fracture, but can also involve other carpal bones such as the triquetrum. These fracture dislocations can be classified in the instabilities in the so-called greater arc injuries.3 The treatment of the carpal fractures itself, however, usually follows the guidelines of the care of the isolated carpal fracture. The second group of fractures represents the fracture of the remaining carpals, which runs through the carpal bones themselves and thus represents a classic dislocated or nondislocated fracture. The slightest severity of injury is the bony avulsion. This is not rare at the carpal bones where many intrinsic and extrinsic ligaments attach. The most common and universally known is the dorsal triquetrum chip fracture.
27.2 Fracture of Triquetrum
27.2.1 Trauma Mechanism
27.2.2 Classification
27.2.3 Clinical Signs and Tests
27.2.4 Investigatory Examinations
Fig. 27.3). In cases of the body fracture, it is recommendable to have a CT scan to be sure that the fracture is not dislocated and that there is a normal alignment of the carpus.
27.2.5 Possible Concurrent Lesions
27.2.6 Evidence
27.2.7 Author’s Favored Treatment Option
Fig. 27.4). If K-wires have been used, they should be removed after 4 to 8 weeks depending on the X-rays. Depending on the function after immobilization, physiotherapy could be recommendable.
27.2.8 Alternative Treatment Options
27.2.9 Prognosis
27.3 Fracture of the Pisiform
27.3.1 Trauma Mechanism
27.3.2 Classification
27.3.3 Clinical Signs and Tests
27.3.4 Investigatory Examinations
Fig. 27.5). In X-ray view, the pisiform bone is free from overlapping of other bones and the diagnosis can usually be made without further investigations. Only in the rare case of an unclear situation, a CT scan can be performed.
27.3.5 Possible Concurrent Lesions
27.3.6 Evidence
27.3.7 Author’s Favored Treatment Option
27.3.8 Alternative Treatment Options
27.3.9 Prognosis
27.4 Fracture of the Lunate
27.4.1 Trauma Mechanism
Fig. 27.6). Another condition, which is not really a lunate fracture, is the bony avulsion of the dorsal scapholunate (SL) ligament, which looks like a small fracture, but indeed is the SL rupture which leads to malalignment of the carpus with dorsal intercalated segmental instability (DISI) deformity. Because of this fact and the classification of five different acute fracture types, there is no typical trauma mechanism defined. So, there can be shear, compression, and hyperextension forces.
27.4.2 Classification
27.4.3 Clinical Signs and Tests
27.4.4 Investigatory Examinations
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