The Effect of Metacarpophalangeal Joint Hyperextension on Outcomes in the Surgical Treatment of Carpometacarpal Joint Arthritis.

Purpose In the surgical treatment of thumb carpometacarpal (CMC) joint arthritis, the effect of mild preoperative metacarpophalangeal (MCP) hyperextension on postoperative functional outcomes is unknown. We sought to examine outcomes after surgical treatment of CMC arthritis in patients with and without mild preexisting MCP deformity. Methods A retrospective review was conducted to analyze the functional outcomes of patients treated for CMC arthritis at a single institution from March 1998 to May 2009. All patients were treated with one of two standard CMC arthroplasty procedures-either ligament reconstruction tendon interposition (LRTI) or a Weilby procedure-and none had additional procedures to address MCP hyperextension. Pre- and postoperative assessments included pinch and grip strength, degree of MCP hyperextension, and thumb radial and palmar abduction. A t -test was used to assume unequal variances. Results A total of 203 patients were followed for an average of 27.3 months. Patients were divided into two groups: (1) patients without preoperative MCP hyperextension (167 patients) and (2) patients with mild but untreated preoperative MCP hyperextension (≤ 30 degrees; 36 patients). All patients underwent either a Weilby procedure (118 patients) or an LRTI; 85 patients). The main difference between techniques was the use of the abductor pollicis longus tendon as a post to secure the flexor carpi radialis (Weilby) or the use of a bone tunnel in the first metacarpal (LRTI). Analysis of the preoperative data showed no difference in the baseline parameters among both the groups, with the exception of MCP hyperextension. Postoperatively, neither the type of CMC procedure nor the presence of MCP hyperextension demonstrated any significant differences in key pinch, tip pinch, grip strength, and radial or palmar abduction of the thumb between the groups. Conclusion There were no statistically significant differences in improvement of functional outcomes after surgery when comparing patients without preoperative MCP hyperextension to patients with untreated MCP hyperextension of less than 30 degrees. Level of Evidence Level III, retrospective comparative study.

Long-Term Results of Mandibular Distraction Osteogenesis with a Resorbable Device in Infants with Robin Sequence: Effects on Developing Molars and Mandibular Growth.

BACKGROUND: Mandibular distraction osteogenesis with a unidirectional resorbable device is an effective treatment option for severe upper airway obstruction in infants with Robin sequence. Long-term effects, especially with regard to tooth development and mandibular outgrowth, are not known. METHODS: Robin sequence infants with a follow-up of greater than or equal to 5 years were included. Baseline characteristics were extracted from medical records. Panoramic and lateral cephalometric radiographs were analyzed and patients were recalled for physical examination. RESULTS: Ten infants underwent mandibular distraction osteogenesis at a mean age of 3.7 months (median, 19 months; range, 11 days to 27 months). Mean length of follow-up was 6.8 years (range, 5.0 to 7.9 years). Ten Robin sequence infants without mandibular distraction osteogenesis (mean length of follow-up, 7.4 years; range, 6.7 to 8.9 years) were the controls. Shape anomalies, positional changes, and root malformations of molars were seen significantly more often than in the control group (p = 0.007, p = 0.009, and p = 0.043, respectively). Mandibular length was shorter (p = 0.030), but mandibular ramus height was comparable (p = 0.838) with that of the non-mandibular distraction osteogenesis group. Compared with healthy controls, all Robin sequence infants had a significantly shorter mandible. CONCLUSIONS: Mandibular distraction osteogenesis with a resorbable system reveals overall good short- and long-term results, but the effects on developing molars and mandibular outgrowth likely necessitate secondary procedures. This factor should be considered when deciding on treatment options and counseling of parents. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Decellularization of a Fasciocutaneous Flap for Use as a Perfusable Scaffold.

BACKGROUND: The aim of the current study was to determine whether a rat fasciocutaneous flap could be decellularized using detergent perfusion and/or agitation methods while preserving the integrity of the extracellular matrix and circulatory networks. METHODS: Superficial inferior epigastric arterial flaps of 50 rats were randomly divided into the following 5 groups: (1) normal; (2) agitation in sodium dodecyl sulfate (SDS) for 72 hours (72h-AG); (3) perfusion and agitation with SDS for 12 hours (12h-PE-AG); (4) perfusion and agitation with SDS for 24 hours (24h-PE-AG); and (5) perfusion and agitation with SDS for 72 hours (72h-PE-AG). These flaps were evaluated by gross morphology, histology, integrity of the microcirculatory networks, and DNA quantification. RESULTS: The DNA content of the normal flap was 1.53 µg/mg. The decellularized flaps had significantly reduced DNA contents: 72h-AG (0.55 µg/mg), 12h-PE-AG (0.52 µg/mg), 24h-PE-AG (0.23 µg/mg), and 72h-PE-AG (0.17 µg/mg). The DNA contents in both the 24h-PE-AG and 72h-PE-AG groups were significantly less than that of 72h-AG and 12h-PE-AG groups. These findings were confirmed by histology and gross morphology. The integrity of the extracellular matrix and vascular system was preserved as measured by collagen and elastin stains in the 4 decellularized groups. Despite the histological appearance of vessel integrity, none of the flaps maintained physiologic vascular integrity by closed-loop circulation. CONCLUSIONS: A combination of perfusion and agitation for 24 hours or longer effectively decellularized the fasciocutaneous portion of composite tissue flaps and removed DNA content from the flap in our rat model with well-preserved vascular structure. This combined technique was superior to agitation alone. However, closed-loop circulation could not be preserved after decellularization with perfusion and/or agitation methods.