A 14-year-old adolescent boy presented to our clinic 5 months after undergoing treatment at an outside facility for a right small finger proximal phalanx fracture with intra-articular extension (▶Fig. 38.1). He was treated with open reduction and pin fixation. He initially did well; however, upon returning to competitive baseball, he was hit by a ball and refractured his finger approximately 4 months after initial injury. Follow-up films showed poor position and he was referred to our clinic. At the time of examination, the patient has some pain at the proximal phalanx, but the primary complaint was stiffness. He finds it difficult to hold a baseball bat properly and notes decreased grip strength.
Inspection of the right small finger reveals radial deviation at the proximal interphalangeal (PIP) joint. The digit is swollen with mild tenderness of the proximal phalanx. There is a well-healed previous dorsal incision. Motion at the PIP joint is 30 to 55 degrees with an intact neurovascular examination.
Fig. 38.1 (a–d) Films at the time of presentation to clinic. Note the rotational deformity of the proximal phalanx with step-off at the joint line and loss of height of the radial condyle.
The patient presents with a postoperative intra-articular angulated proximal phalanx malunion. Articular malunions can result in pain, deformity, joint stiffness, and progressive degenerative joint disease as highlighted by this case.
Phalangeal extra-articular malunions of significant amount may lead to rotational deformity of the fingers, pain due to distortion of the joint, alteration of the musculotendinous balance, and/or reduction of grip strength. Intra-articular malunions may cause joint surface irregularities, synovitis, capsule laxity or stiffness, and ultimately arthritis.
Weighing the clinical significance of a malunion should take into account these factors. Of note, malunion of the thumb, middle, and distal phalanges of the fingers usually yields lesser problems than those located in the proximal phalanx. A young, active patient may require a different management strategy than an older or sedentary patient. Malunions requiring surgical correction are usually infrequent in any one surgeon’s practice; therefore, management and technical preferences often rely on the individual surgeon’s judgment.
Options for surgical correction include an extra-articular versus intra-articular osteotomy. Extra-articular osteotomy can correct the alignment, but lacks the ability to address articular incongruity. Intra-articular osteotomy can yield powerful correction of articular deformity; however, it can be a complex procedure with increased risk for stiffness or arthritis.
Timing of osteotomy varies. For extra-articular fractures, an osteotomy through the fracture plane should be addressed at weeks 6 to 8 from injury. Once the patient has passed the 8-week mark, osteotomy outside of the fracture plane should be considered. Articular osteotomies made through the plane of fracture should be done as soon as possible and ideally sooner than 6 months. Articular osteotomy outside of the fracture plane is difficult and not typically recommended.
Various osteotomies to correct articular malunion have been described. A few notable descriptions include extra-articular osteotomy by Pieron, Froimson, and Harness et al, and intraarticular correction as described by Light and Teoh et al.
This patient was treated with intra-articular sliding advancement osteotomy technique, a modification of the technique described by Teoh et al. Stabilization was achieved with the use of allograft bone and Kirschner’s wires (K-wires) for fixation.
Regional block can be considered. The patient is placed supine and the operative extremity prepped in the usual fashion. Tourniquet is elevated to improve visualization. In this case, previous dorsal longitudinal incision was used over the PIP joint. Thick soft-tissue flaps are raised. The extensor mechanism is visualized. An extensor tendon–splitting technique can be used with a longitudinal split in the midline. Subperiosteal dissection is taken to the distal proximal phalanx and proximal middle phalanx for visualization of the joint line and the malunion (▶Fig. 38.2a). Any nonunion evident should be debrided gently using rongeur and curette (▶Fig. 38.2b). Consider sending a sample of the nonunion for culture to rule out occult infection as a source of non- or malunion.
The articular segment is gently mobilized (▶Fig. 38.3a). If fracture has healed, a small osteotomy is made proximally to slide the malreduced articular segment distally. Tricks include using a 0.035-inch K-wire in the fragment as a joystick, as well as a piercing reduction clamp to reduce the articular segment anatomically. Another trick is to look down the joint line in the “shotgun” approach to visualize the overall articular reduction. The reduction is held with multiple K-wires to ensure appropriate stability (▶Fig. 38.3b). Alternatively, small screws could be considered as described by Teoh et al.
Allograft bone is used to backfill the void and provide additional support for the articular reduction. Check the final fixation construct with direct visualization and fluoroscopy (▶Fig. 38.4). K-wires can be cut under the skin to allow for potential removal at a later date. The extensor mechanism is closed using nonabsorbable suture and skin is closed in an interrupted fashion. The patient is immobilized for 4 to 6 weeks to allow osteotomy healing and then early motion is begun.