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A three-year old patient with symbrachydactyly (didactyly type) presented with a little finger that was too short to allow pinching and consisting of a floppy soft-tissue envelope with hypoplastic phalanges, although the thumb was functional. As the proximal phalanx was too small to permit distraction lengthening or conventional bone grafting, on-top plasty using a 4th metacarpal graft with a cartilage head was undertaken for lengthening the proximal phalanx of the little finger for pinch reconstruction. At ten weeks after surgery, the patient achieved satisfactory pinch function due to the lengthened and bone-stabilised postoperative digit and reconstruction of functional proximal interphalangeal joint. In addition, the grafted metacarpal demonstrated satisfactory bone growth throughout the six-year follow-up period.

Background: Chronic, post-traumatic, avulsion of the proximal interphalangeal (PIP) joint volar plate represents a disabling lesion. The purpose of this report is to describe a flexor digitorum superficialis (FDS) tenodesis using a mini-bone anchor inserted into the proximal phalanx, and its clinical outcome.

Methods: 15 patients with chronic post-traumatic hyperextension instability of the PIP joint were treated surgically. From the first post-operative day patients were invited to start an early gradual joint active motion, wearing an extension block splint. Forty days after surgery, clinical evaluations were carried out, including: joint stability, pain and range of motion (ROM). The use of a circumferential splint was recommended for two further months, avoiding strenuous manual activities. The range of motion, time lost at work and the functional results were recorded six months after surgery.

Results: At last follow up, 7 of the 13 reviewed patients presented an excellent functional recovery, with complete resolution of pain and stability with attainment of ROM comparable to the contralateral finger. The others 6 patients obtained good results, with remission of the functional impairment and pain, with either residual hyperextension or flexion contracture. There was one case of recurrence consecutively to a premature traumatic work-related activity.

Conclusions: The FDS tenodesis via a bone anchor, combined with early active PIP joint protected motion, was shown in this study to be effective and reliable.

Background: Unconstrained pyrocarbon and metal-on-polyethylene (MoP) proximal interphalangeal (PIP) joint arthroplasty is an increasingly popular alternative to silicone implants and arthrodesis. This systematic review appraises their outcomes.

Methods: Thirty studies comprising 1,324 joints (813 pyrocarbon, 511 MoP) were included. Mean patient age was 59 years (38–78) and mean follow-up period was 54 months (12–118).

Results: There were mean improvements of 4.5 points (2–6.9) in pain visual analogue score, 10.5° (−26 to 58) in range of motion (ROM), 3.1 kg (−4 to 7) in grip strength, 0.6 kg (−1.5 to 2) in pinch strength and 18 points (−3 to 29) in the disabilities of the arm, shoulder and hand score, with no significant differences between implant types. ROM gains deteriorated over time. Clinical complications were frequent (23%) and significantly more common with pyrocarbon, as were radiographic complications. However, most were mild-moderate and did not necessarily correlate with negative outcomes or dissatisfaction. Overall re-operation rate was 21%, and revision rate 11%, both more frequent with pyrocarbon. Most revisions were within 24 months, beyond which survival was maintained up to 10 years.

Conclusions: Unconstrained PIP joint arthroplasty is effective in improving pain scores, active ROM, grip/pinch strength and patient-reported outcome measures, particularly in patients with osteoarthritis. Results are generally maintained at least to the medium term, although gains diminish in the longer term. Complication and early revision rates are high, particularly with pyrocarbon implants. Most patients express positive attitudes to arthroplasty, with significant improvements in patient-reported outcome measures for both pyrocarbon and MoP implants. Patients with post-traumatic and inflammatory arthropathy are generally less satisfied. There is currently insufficient data to recommend one implant type over another, although the early-to-medium term results of MoP implants are promising. Prospective surveillance via small joint registries is recommended.

Level of Evidence: Level III (Therapeutic)

Fusion of the proximal interphalangeal joint (PIPJ) after failed arthroplasty may be challenging in view of bone loss at the ends of the proximal phalanx and the middle phalanx. This might require the use of a structural bone graft to fill the defect and avoid shortening of the digit. Although several methods have been described for primary PIPJ fusion, none of these methods addresses bone loss at this joint. We use a tricortical iliac crest bone graft fashioned to provide the required angulation at the fusion site. A dorsal plate is used to fix the fusion mass and obliquely placed screws provide sequential compression at both ends of the bone graft. We have performed this technique safely in three patients with no complications.

Level of Evidence: Level V (Therapeutic)