Augmented tendon Achilles repair using a tissue reinforcement scaffold: a biomechanical study.

BACKGROUND: Missed or chronic Achilles tendon ruptures may have muscle atrophy and tendon retraction resulting in a defect that must be augmented with endogenous or exogenous materials. The Artelon® Tissue Reinforcement (ATR) scaffold is a readily available synthetic degradable poly(urethane urea) material used to augment tendon repair. The objective of this study was to compare human cadaveric Achilles tendon repairs with and without ATR. MATERIALS AND METHODS: Eighteen fresh frozen human cadaver limbs were dissected and the tendon transected 2 cm proximal to the calcaneal insertion. The control group of nine specimens was repaired with sutures, while the experimental group was repaired with sutures and reinforced with a tubularized patch of ATR. Specimens were tested for ultimate load to failure in an Instron machine after preloading to 10 N followed by cyclic loading for 20 cycles from 2 to 30 N. RESULTS: The ultimate load to failure in the control group was a mean of 248.1 N ± 19.6 (202 to 293 at 95% CI) versus 370.4 N ± 25.2 (312 to 428 at 95% CI) in the ATR group. The ultimate load to failure was 370.4 ± 25.2 N (312 to 428 at 95% CI) and 248.1 ± 19.6 N (202 to 293 at 95% CI) in the experimental and control groups, respectively (p = 0.0015). Creep of the ATR augmented group was 2.0 ± 0.5 mm, compared to 3.1 ± 1.1 mm for the control group (p = 0.026). CONCLUSION: ATR provided a statistically significant improvement in load to failure when compared to control specimens in a cadaver model. CLINICAL RELEVANCE: This finding may allow for development of more aggressive rehabilitation techniques following chronic Achilles tendon repairs.

First metatarsophalangeal hemiarthroplasty for hallux rigidus.

There is a paucity of objective information in the literature about first metatarsophalangeal (MTP) hemiarthroplasty. The authors postulate that it is a reasonable treatment option for severe hallux rigidus in selected patients. Twenty-two elective first MTP hemiarthroplasties were performed on 20 patients that met the inclusion criteria. Pre- and postoperative evaluations were done using the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score, visual analogue scale (VAS) pain score, range of motion (ROM) measurements, and radiographs. Average ROM and dorsiflexion improved by 15° and 8°, respectively. VAS pain scores improved from 5 to 2.5 after six weeks. Painless ambulation occurred after six weeks, with maximum improvement by six months. After 24 months, two patients had pain at the surgical site interfering with function, leading to an unsatisfactory result that required conversion to arthrodesis. First MTP hemiarthroplasty for severe hallux rigidus can be considered an alternative to fusion in properly selected patients who wish to maintain a functional range of motion.