Nonvascularized osteoarticular allograft replacement of the proximal interphalangeal joint after extensive loss of bone, joint, and extensor tendon

Massive bone allograft engineered with autologous vessels: A new perspective for the future

Reconstruction is very important to ensure good function and quality of life after bone tumor resection. For metacarpals and phalanges, amputation and toe transfer are the gold-standard indications; nevertheless, allograft reconstruction must also be taken into account. Unfortunately, because of its inert biological behavior, it undergoes progressive resorption, with frequent fracture. Several attempts have been made to induce new vascularization in massive bone allograft, with poor results. However, neo-angiogenesis was reported with vascular loops, and we therefore hypothesized that heterologous graft integration could be enhanced by creating a vascular loop through the graft. A 50-year-old male with chondrosarcoma of the ring finger of the left hand underwent wide resection. An allogenic middle phalanx of comparable size was then prepared to fill the defect. Two small windows were performed proximally and distally on the radial surface of the allogenic phalanx, and a 4 cm-long vein graft was inserted inside the medullary canal. Metacarpophalangeal joint stability was achieved by collateral ligament reconstruction with micro-anchors. The distal part of the allograft was then stabilized to the middle phalanx with a 1.5 mm-thick micro-plate and screws. The radial proper palmar digital artery was proximally and distally sutured end-to-end to the vein graft, under microscopy. At 12-month follow-up, the allograft was fused, and histology performed at plate removal at 18 months revealed viable spindle cells with osteoblastic differentiation, without evidence of atypia, in a dense fibrous stroma. At 22 months' follow-up, the patient was apparently disease-free, and satisfied with his manual function.

Metacarpal Aneurysmal Bone Cyst En Bloc Resection Reconstructed With Osteoarticular Allograft

Aneurysmal bone cysts are large lytic lesions that appear most often around metaphyseal bone. The lesions are locally aggressive with high recurrence rates. Therefore, wide resection is commonly necessary, leading to challenging reconstruction of the defect, especially when the articular surface is involved. We present a case of an aneurysmal bone cyst of the fourth metacarpal, treated with an en bloc resection and reconstruction with a metacarpal osteoarticular allograft. At 8 years after surgery, the patient has shown no signs of recurrence, but radiographic articular reabsorption was noted. However, the patient showed an excellent outcome with a satisfactory active range of motion and grip strength. Despite potential complications, osteoarticular allograft is a feasible alternative when autologous osteoarticular reconstruction is not an option.

Recurrent Metacarpal Enchondroma Treated With Strut Allograft: 14-year Follow-up

Enchondroma of the hand is a common lesion with a recurrence rate of up to 13.3% after curettage and bone grafting. Pathologic fractures often occur. Although allograft bone chips are widely used in the surgical treatment of enchondroma, the use of structural allograft bone has not been reported before. This case report presents a recurrent enchondroma of the fifth metacarpal with pathologic fracture in a 13-year-old girl who had 2 previous interventions and 2 more interventions for other enchondromas in the same hand. These interventions consisted of curettage and autogenous iliac crest bone grafting. The metacarpal diaphysis was resected and reconstructed with an intercalary freeze-dried strut allograft fibular bone segment to avoid further donor graft site morbidity. At 14 years of follow-up, the patient had full range of motion of the hand, with no symptoms, and the allograft bone had been incorporated completely, with no recurrence of the tumor. With strut allograft bone, healing occurs by creeping substitution at its ends that is limited to a few millimeters. Limited vascularization also occurs on the allograft surface, leaving most of the allograft segment devoid of vascularity and leading to the complications seen in massive bone allografts. However, because of their thin cortices and decreased total volume, smaller bone allografts show higher rates of osteointegration and revascularization. In selected cases, a strut allograft bone may be considered a suitable material for long-term reconstruction of the hand after enchondroma excision, especially in young patients, who have increased healing potential compared with older patients.

Possibility of the hamatum carpometacarpal joint as a new joint donor site for interphalangeal joint restoration

OBJECTIVE

This research investigates the anatomic basis for the repair and reconstruction of hand joints using transposition of the carpometacarpal (CMC) joint of the hamatum.

METHODS

The morphology and structure of the CMC joints of the hamatum and the base joints of the middle phalanx were observed on 22 freshly frozen wrist specimens at Shanghai 6th People's Hospital Research Institute of Microsurgery. The volar dorsal dia, radioulnar dia, depth of concave, and area of the joints were measured. Data were obtained through statistical analysis, and the resemblance of joints was compared in terms of morphology, structure, area, length, and diameter.

RESULTS

The radioulnar dia of the CMC joints of the hamatum (13.54 ± 1.15 mm) did not exhibit any evident differences in the middle phalanx of the forefinger, middle finger, and ring finger, and in the distal phalanx of the thumb. The volar dorsal dia of the CMC joints of the hamatum (10.71 ± 0.93 mm) exhibited an evident difference in the middle phalanx of the ring finger. In all fingers, the depth of the ulnar and radial concave of the CMC joints of the hamatum (1.30 ± 0.08 and 0.95 ± 0.05 mm, respectively) and the area of the CMC joints of the hamatum (139.89 ± 5.44 mm(2)) showed an evident difference.

CONCLUSION

The CMC joint of the hamatum could be considered a new and viable joint donor site that could be used to repair and reconstruct the base joints of the middle phalanx.