STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To investigate the effects of instrument-assisted cross-fiber massage (IACFM) on tissue-level healing of knee medial collateral ligament (MCL) injuries. BACKGROUND: Ligament injuries are common and significant clinical problems for which there are few established interventions. IACFM represents an intervention that may mediate tissue-level healing following ligament injury. METHODS: Bilateral knee MCL injuries were created in 51 rodents, while 7 rodents were maintained as ligament-intact, control animals. IACFM was commenced 1 week following injury and introduced 3 sessions per week for 1 minute per session. IACFM was introduced unilaterally (IACFM-treated), with the contralateral, injured MCL serving as an internal control (nontreated). Thirty-one injured animals received 9 ACFM treatments, while the remaining 20 injured animals received 30 treatments. Ligament biomechanical properties and morphology were assessed at either 4 or 12 weeks postinjury. RESULTS: IACFM-treated ligaments were 43.1% stronger (P<.05), 39.7% stiffer (P<.01), and could absorb 57.1% more energy before failure (P<.05) than contralateral, injured, nontreated ligaments at 4 weeks postinjury. On histological and scanning electron microscopy assessment, IACFM-treated ligaments appeared to have improved collagen fiber bundle formation and orientation within the scar region than nontreated ligaments. There were minimal differences between IACFM-treated and contralateral, nontreated ligaments at 12 weeks postinjury, although IACFM-treated ligaments were 15.4% stiffer (P<.05). CONCLUSION: IACFM-accelerated ligament healing, possibly via favorable effects on collagen formation and organization, but had minimal effect on the final outcome of healing. These findings are clinically interesting, as there are few established interventions for ligament injuries, and IACFM is a simple and practical therapy technique.

J Orthop Sports Phys Ther 2009;39(7):506-514, Epub 24 February 2009. doi:10.2519/jospt.2009.2997

KEY WORDS: biomechanics, complementary therapies, medial collateral ligament, physical therapy, sports medicine

STUDY DESIGN: Experimental laboratory study. OBJECTIVES: To quantify and compare electromyographic signal amplitude of the gluteus maximus and gluteus medius muscles during exercises of varying difficulty to determine which exercise most effectively recruits these muscles. BACKGROUND: Gluteal muscle weakness has been proposed to be associated with lower extremity injury. Exercises to strengthen the gluteal muscles are frequently used in rehabilitation and injury prevention programs without scientific evidence regarding their ability to activate the targeted muscles. METHODS: Surface electromyography was used to quantify the activity level of the gluteal muscles in 21 healthy, physically active subjects while performing 12 exercises. Repeated-measures analyses of variance were used to compare normalized mean signal amplitude levels, expressed as a percent of a maximum voluntary isometric contraction (MVIC), across exercises. RESULTS: Significant differences in signal amplitude among exercises were noted for the gluteus medius (F_5,90 = 7.9, P<.0001) and gluteus maximus (F_5,95 = 8.1, P<.0001). Gluteus medius activity was significantly greater during side-lying hip abduction (mean ± SD, 81% ± 42% MVIC) compared to the 2 types of hip clam (40% ± 38% MVIC, 38% ± 29% MVIC), lunges (48% ± 21% MVIC), and hop (48% ± 25% MVIC) exercises. The single-limb squat and single-limb deadlift activated the gluteus medius (single-limb squat, 64% ± 25% MVIC; single-limb deadlift, 59% ± 25% MVIC) and maximus (single-limb squat, 59% ± 27% MVIC; single-limb deadlift, 59% ± 28% MVIC) similarly. The gluteus maximus activation during the single-limb squat and single-limb deadlift was significantly greater than during the lateral band walk (27% ± 16% MVIC), hip clam (34% ± 27% MVIC), and hop (forward, 35% ± 22% MVIC; transverse, 35% ± 16% MVIC) exercises. CONCLUSION: The best exercise for the gluteus medius was side-lying hip abduction, while the single-limb squat and single-limb deadlift exercises led to the greatest activation of the gluteus maximus. These results provide information to the clinician about relative activation of the gluteal muscles during specific therapeutic exercises that can influence exercise progression and prescription.

J Orthop Sports Phys Ther 2009;39(7):532-540, Epub 24 February 2009. doi:10.2519/jospt.2009.2796

KEY WORDS: EMG, hip, gluteus medius, gluteus maximus

STUDY DESIGN: Experimental laboratory study supplemented by a case series. OBJECTIVES: (1) To assess the effect of a 4-week intervention with a full-length insert on functional outcomes in patients with midfoot arthritis; (2) to examine the effect of the custom molded three-quarter-length (3Q) and full-length (FL) carbon graphite insert on plantar loading in patients with midfoot arthritis. BACKGROUND: Given the coexistence of pain and lower-arched foot alignment in patients with midfoot arthritis, arch-restoring orthotic devices such as the 3Q insert are frequently recommended. However, patients continue to report foot pain despite using the 3Q insert. The FL insert has been proposed as an alternative, but objective data examining its efficacy are lacking. METHODS: Twenty female patients with midfoot arthritis participated in the study. Functional outcomes were assessed using the Foot Function Index-Revised (FFI-R). Plantar loading during walking was measured in the following conditions: shoe only, shoe with 3Q insert, and shoe with FL insert. Repeated-measures analyses of variance with post hoc analyses were used for statistical analysis. RESULTS: FL insert use for 4 weeks resulted in a 12% improvement in total FFI-R score (mean ± SD before, 35.6 ± 10.9; after, 31.1 ± 9.8 [P = .03]). FL insert use resulted in a 20% reduction in medial midfoot average pressure loading (mean ± SD, 64.8 ± 20.4 and 51.0 ± 15.4 kPa, with 3Q and FL insert respectively [P = .015]) and an 8.5% reduction in medial midfoot contact time (mean ± SD, 84.9% ± 6.4% and 76.4% ± 7.1% of stance, with 3Q and FL insert respectively [P<.01]), compared to the 3Q insert. No differences in plantar loading were discerned between the shoe-only and FL conditions. CONCLUSION: Symptomatic improvement in patients with midfoot arthritis treated with a FL insert was accompanied by reduced magnitude and duration of loading under the medial midfoot. These preliminary outcomes suggest that the FL insert may be a viable alternative in the conservative management of patients with midfoot arthritis. LEVEL OF EVIDENCE: Therapy, level 4.

J Orthop Sports Phys Ther 2009;39(7):522-531. doi:10.2519/jospt.2009.2900

KEY WORDS: Lisfranc, orthoses, tarsometatarsal

STUDY DESIGN: Case series. CASE DESCRIPTION: Five consecutive collegiate Division I wrestlers, with a mean age of 20.2 years (range, 18-22 years), were treated postsurgical stabilization to address posterior glenohumeral joint instability. All received physical therapy postoperatively, consisting of range-ofmotion, strengthening, and plyometrics exercises, neuromuscular re-education, and sport-specific training. Functional outcome scores using the Penn Shoulder Score questionnaire were recorded at postsurgical initial evaluation and discharge. Isometric shoulder strength, measured with a handheld dynamometer at discharge, was compared with measurements made during preseason screening. OUTCOMES: Postsurgery, upon initial physical therapy evaluation, scores on the Penn Shoulder Score questionnaire ranged from 37 to 74 out of 100. All 5 wrestlers improved with rehabilitation such that their scores at discharge ranged from 81 to 91 out of 100. Mean external rotation-internal rotation strength ratio for the involved shoulder was 73.5% (range, 55.9%-88.7%) preseason and 80.9% (range, 70.2%-104.1%) postrehabilitation. Four patients were able to return to wrestling over a period of 1 season, with no episodes of reinjury to their surgically repaired shoulder. DISCUSSION: Current research on posterior glenohumeral instability is limited, due to the relatively rare diagnosis and infrequent need for surgical intervention. Providing a structured physical therapy program following this surgical procedure appeared to have assisted in a return to full functional activities and sports. LEVEL OF EVIDENCE: Therapy, level 4.

J Orthop Sports Phys Ther 2009;39(7):550-559, Epub 24 February 2009. doi:10.2519/jospt.2009.2952

KEY WORDS: dislocation, dynamic stability, glenohumeral, joint instability, strength

The JOSPT offers invited reviews of current titles. The March 2009 column includes 6 reviews of the following books: Synopsis of Spine Surgery; Spinal Cord Injuries: Management and Rehabilitation; Essentials of Kinesiology for the Physical Therapist Assistant; Imaging in Rehabilitation; Musculoskeletal Manual Medicine: Diagnosis and Treatment; and Dictionary of Orthopedic Terminology.