Clinical Outcomes of an Initial 3-month Trial of Conservative Treatment for Femoroacetabular Impingement.

BACKGROUND: Femoroacetabular impingement (FAI) can be managed either conservatively or by a surgical correction of the deformity causing impingement. However, there is insufficient evidence to justify an immediate surgical treatment in all symptomatic patients, and the role of a nonoperative treatment is unclear. This study evaluates the role of conservative treatment for FAI. MATERIALS AND METHODS: 87 patients (102 hips) diagnosed as FAI between January 2011 and May 2012 were included in this retrospective study. All patients underwent an initial 3-month conservative treatment followed by arthroscopic hip surgery if symptoms did not improve. Clinical outcome scores (modified Harris Hip Score, nonarthritic hip score, and Western Ontario and McMaster Universities Arthritis Index) were evaluated at baseline and at the end of followup, and scores were compared between the nonsurgical and surgical groups. RESULTS: The final analysis included 83 patients (55 men, 28 women; 97 hips) because four patients were lost to followup. The average age was 45.1 years and 14 patients had bilateral symptomatic FAI. After an initial conservative treatment averaging 27.5 months (range 24-36 months), 53 hips (54.6%) could perform normal daily activities. The nonsurgical group had significant improvements in all clinical scores at the end of followup (P < 0.001). Forty four hips (45.4%) were unresponsive to conservative treatment and underwent arthroscopic hip surgery with subsequent significant improvements in clinical scores (P < 0.001). At the end of followup, there were no significant differences in clinical scores between the two groups. CONCLUSION: An initial trial of conservative treatment of sufficient length should be considered for FAI patients before surgical intervention.

Arthroscopic Reduction and Internal Fixation for Pipkin Type I Femoral Head Fracture: Technical Note.

Femoral head fractures after posterior dislocation of the hip are uncommon and are conventionally treated by an open method. Hip arthroscopy can be a valuable treatment option for the management of femoral head fractures. Arthroscopy allows for a less invasive option when compared with arthrotomy and can allow faster recovery with minimal soft-tissue injury. We describe the arthroscopic reduction and internal fixation of Pipkin type I femoral head fractures with a detailed stepwise description of the surgical technique, including technical pearls and pitfalls, potential complications, and advantages and disadvantages.

What is the Prevalence of Radiographic Hip Findings Associated With Femoroacetabular Impingement in Asymptomatic Asian Volunteers?

BACKGROUND: Morphologic features of the proximal femur reminiscent of those seen in patients with femoroacetabular impingement (FAI) have been reported among asymptomatic individuals in Western populations, but whether this is the case in Asian populations is unknown. QUESTIONS/PURPOSES: The purpose of this study was to determine the prevalence of radiographic findings in the proximal femur that are consistent with FAI in asymptomatic Korean volunteers. METHODS: Two hundred asymptomatic volunteers with no prior hip surgery or childhood hip problems underwent three-view plain radiographs (pelvis AP view, Sugioka view, and 45° Dunn view) of both hips. There were 146 hips from male volunteers and 254 hips from female volunteers in the study. The mean age of all participants was 34.7 years (range, 21-49 years). Cam-type morphologic features were defined as the presence of the following on one or more of the three views: pistol-grip morphologic features, an osseous bump at the femoral head-neck junction, flattening of the femoral head-neck offset, or alpha angle greater than 55°. Pincer-type morphologic features were determined by radiographic signs, including crossover sign, deficient posterior wall sign, or lateral center-edge angle greater than 40°. RESULTS: The prevalence of cam-type morphologic features seen on at least one radiograph was 38% (male, 57%; female, 26%). The prevalence of cam-type features (at least one positive cam-type feature) was 2.0% (male, 6%; female, 0%) on the pelvic AP view, 24% (male, 36%; female, 17%) on the Sugioka view, and 30% (male, 47%; female, 20%) on the 45° Dunn view. The prevalence of pincer-type morphologic features (at least one positive pincer-type feature) was 23% (male, 27%; female, 21%) on the pelvic AP view. CONCLUSION: The prevalence of FAI-related morphologic features in asymptomatic Asian populations was comparable to the prevalence in Western populations. Considering the high prevalence of radiographic hip findings reminiscent of FAI in asymptomatic Asian populations, it will be important to determine whether FAI-related morphologic features are a cause of hip pain when considering surgery in Asian patients.

Experimental measurement of tympanic membrane response for finite element model validation of a human middle ear.

The middle ear consists of a tympanic membrane, ligaments, tendons, and three ossicles. An important function of the tympanic membrane is to deliver exterior sound stimulus to the ossicles and inner ear. In this study, the responses of the tympanic membrane in a human ear were measured and compared with those of a finite element model of the middle ear. A laser Doppler vibrometer (LDV) was used to measure the dynamic responses of the tympanic membrane, which had the measurement point on the cone of light of the tympanic membrane. The measured subjects were five Korean male adults and a cadaver. The tympanic membranes were stimulated using pure-tone sine waves at 18 center frequencies of one-third octave band over a frequency range of 200 Hz ~10 kHz with 60 and 80 dB sound pressure levels. The measured responses were converted into the umbo displacement transfer function (UDTF) with a linearity assumption. The measured UDTFs were compared with the calculated UDTFs using a finite element model for the Korean human middle ear. The finite element model of the middle ear consists of three ossicles, a tympanic membrane, ligaments, and tendons. In the finite element model, the umbo displacements were calculated under a unit sound pressure on the tympanic membrane. The UDTF of the finite element model exhibited good agreement with that of the experimental one in low frequency range, whereas in higher frequency band, the two response functions deviated from each other, which demonstrates that the finite element model should be updated with more accurate material properties and/or a frequency dependent material model.