Necrotizing Soft Tissue Infection Following a Closed Distal Radius Fracture: A Case Report and Literature Review.

Necrotizing soft tissue infections (NSTIs), characterized by extensive soft tissue destruction, are rare but life-threatening. We present a case of a NSTI in a healthy 65-year-old woman following a closed distal radius fracture. The patient presented with severe pain, fever, and lethargy 4 days after her index injury, with physical examination of the right upper limb revealing erythema and swelling to the mid-humeral level and blisters of the fingers and hand. Multiple surgical debridements were required to control the infection, which was caused by Streptococcus pyogenes. This case highlights the rapid progression and devastating consequences of NSTI, which can occur even in the setting of closed injuries in patients without comorbidities. Prompt diagnosis, early surgical intervention, and appropriate antimicrobial therapy are crucial in managing this pathology.Level of Evidence: Level 5.

Hemi-hamate Arthroplasty for Base of Middle Phalanx Fracture: A Systematic Review.

Intra-articular fracture dislocations of the base of the middle phalanx are complex and debilitating injuries that present a management conundrum when nonreconstructable. Hemi-hamate arthroplasty (HHA) is a treatment modality of particular use in the setting of highly comminuted fractures. This systematic review aims to summarize the reported outcomes of HHA in this context. A literature search was conducted using MEDLINE, Embase, and PubMed, yielding 22 studies with 235 patients for inclusion. The weighted mean postoperative range of movement at the proximal interphalangeal joint was 74.3° (range, 62.0°-96.0°) and at the distal interphalangeal joint was 57.0° (range, 14.0°-80.4°). The weighted mean postoperative pain Visual Analog Scale was 1.0 (range, 0.0-2.0). The weighted mean postoperative grip strength was 87.1% (range, 74.5%-95.0%) of the strength on the contralateral side. Posttraumatic arthritis was reported in 18% of cases, graft collapse in 4.2%, and donor site morbidity in 3.0%, with a mean follow-up period of 28.4 months (range, 1-87 months). Hemi-hamate arthroplasty is a reliable and effective technique for the reconstruction of intra-articular base of middle phalangeal fracture dislocations, affording symptomatic relief and functional restoration. Further research is required to assess the true incidence of long-term complications.

Sagittal Band Injuries: A Review and Modification of the Classification System.

Sagittal band injuries, although relatively uncommon, can be difficult to treat. This review provides a contemporary perspective on this pathology, as well as a modification to the classification system. This modification aims to incorporate the spectrum of disease seen, guide treatment, and allow standardization when documenting and describing injuries.

Mechanics of Metacarpophalangeal Joint Extension.

PURPOSE: It is a common belief that extension of the metacarpophalangeal (MCP) joint of the finger is achieved via the sagittal bands acting as a sling or lasso to attach the extensor tendon to the base of the proximal phalanx. The aim of this study was to test the hypotheses that (1) division of the sagittal bands reduces extension force or torque of the MCP joint, and (2) division of the extensor tendon distal to the sagittal band will not affect the extension force or torque of the MCP joint. METHODS: Ten cadaver limbs were secured to a jig to allow for testing of the extension force of the MCP joints of the index, middle, and ring fingers. A 1-kg load was applied to the forearm extensor digitorum communis tendon and the extension force was measured with the MCP joint positioned at 0° (neutral extension) and again at 45° flexion. These measurements were repeated after the sagittal bands were divided in 15 specimens; in the other 15 specimens, the extensor tendon was divided just distal to the sagittal bands. RESULTS: After sagittal band division, extension force was similar in the 2 groups (0.11 N reduction after division with the MCP joints in neutral and 0.14 N in 45° flexion). There was significantly less extension force after division of the extensor tendon in both joint positions (0.95 N reduction after division in neutral extension and 0.66 N in 45° flexion). CONCLUSIONS: The sagittal bands do not primarily extend the MCP as a sling or lasso. The extensor tendon continuation to the extensor hood and middle phalanx is the major extension motor. The MCP joint is extended by the torque generated by the extensor tendon passing the joint carrying a force and possessing an extension moment arm. CLINICAL RELEVANCE: This principle should be correctly understood in the literature to ensure that clinical decisions related to injury and/or repair of the extensor tendon and sagittal bands are based on a sound understanding of their mechanics.

Adhesion formation after flexor tendon repair: comparison of two- and four-strand repair without epitendinous suture.

Increased handling, increased bulk at the repair site and an increase in external suture material may affect adhesion formation and gliding after tendon repair. A previous study(1) showed no significant difference in biomechanical or histopathological measurement of adhesion formation in two- and four-strand repairs combined with an epitendinous suture in the chicken model. In the present study, the flexor digitorum profundus tendon of the middle toe of 47 broiler chickens was cut and repaired with either a single (two-strand) or double (four-strand) modified Kessler core suture without epitendinous suture and immobilised for four weeks. Adhesion formation was measured by biomechanical testing or quantitative and qualitative histopathology. Biomechanical and histological data showed no differences between two- and four-strand repairs. Results did not differ from the previous study which used an epitendinous suture. Adhesion formation is not necessarily increased when multi-strand techniques are used, nor by the placement of an epitendinous suture if care is taken with surgical technique. Individual healing response introduces more variability than an increase in tendon handling by an experienced surgeon.

Adhesion formation after flexor tendon repair: a histologic and biomechanical comparison of 2- and 4-strand repairs in a chicken model.

PURPOSE: Both increased handling and increased bulk at the repair site have been hypothesized as affecting adhesion formation and gliding after tendon repair. Tendons repaired with 2- and 4-strand techniques were compared using both biomechanical and histopathologic measurements to determine the influence of increasing strand number on adhesion formation and gliding. METHODS: The flexor digitorum profundus tendon of the right middle toe of 80 broiler chickens was cut and then repaired with either a single (2-strand) or double (4-strand) modified Kessler core suture, followed by a running epitendinous suture. The limb was immobilized after surgery. Birds were killed at either 3 days or 4 weeks after tendon repair and adhesion formation measured using either biomechanical testing or quantitative and qualitative histology. For biomechanical testing, the tendon was pulled free of the sheath and a force versus displacement curve was generated. Comparisons of peak force and work to peak were made. Histologic specimens were examined by a pathologist blinded to the treatment group who scored the length and density of adhesions and made qualitative observations. RESULTS: Both biomechanical and histologic data showed expected differences in adhesion formation for early (3 days) and late (4 weeks) healing but no significant differences between 2- and 4-strand repairs. Biomechanical testing of 4-week specimens showed a nonsignificant tendency toward greater work required to break adhesions in 4-strand repairs. CONCLUSIONS: Adhesion formation and gliding resistance of tendons after 2- or 4-strand modified Kessler core suture were not significantly different, which suggests that simply increasing the number of strands crossing a repair does not necessarily result in more adhesions or resistance in this model.

Low-intensity ultrasound stimulation in distraction osteogenesis in rabbits.

Low-intensity pulsed ultrasound has been shown to accelerate fracture healing. This experiment investigated its possible role in distraction. Thirty-four New Zealand White rabbits had distraction osteogenesis, followed by low-intensity pulsed ultrasound therapy. Seventeen animals had the ultrasound transducer switched off (controls). Four and 6 weeks postoperatively, tibiae were analyzed using quantitative computed tomography and four-point mechanical testing. Two tibiae from each group had histologic analysis at 4 weeks. No significant differences were identified between regenerates of ultrasound-treated and control groups with respect to bone mineral content, cross-sectional area, and strength. No significant reductions in osteopenia proximal and distal to the regenerate were observed. Histologic observation showed no differences in bone volume fraction, but ultrasound-treated regenerates appeared to have fewer trabeculae of increased thickness, and fewer osteoclasts. The modulation by ultrasound may occur by accelerating endochondral ossification through action on chondrocytes, yet distraction osteogenesis is largely intramembranous. Although ultrasound is proven to be effective in unconstrained systems such as plaster, the current study does not support the role of low-intensity pulsed ultrasound as an adjunct for patients having distraction osteogenesis in a rigid fixator. Additional research is needed to definitively support the use of low-intensity pulsed ultrasound in such situations.