Adhesion rate following hip arthroscopy lowered in part by circumduction exercises

Issue: September 2011

SAN FRANCISCO — A reduction in the rate of adhesions following hip arthroscopy can be achieved through changes in rehabilitation protocol, according to a study presented at the 2011 Annual Meeting of the Arthroscopy Association of North America.

“Revision hip arthroscopy has been described as part of the learning curve in the advancement of the treatment of multiple intra-articular problems,” study author S. Clifton Willimon, MD, said during his presentation. “Intra-articular adhesions have been reported as a cause of continued pain after both open and arthroscopic procedures of the hip.”

Willimon noted that although these adhesions have been reported, the risk factors that could lead to an increased rate of adhesions had not been identified.

Factors for adhesions

Willimon and colleagues analyzed data from the experience of Marc M. Philippon, MD, with primary hip arthroscopies performed between 2005 and 2009. Cases were analyzed individually to see if adhesions were the primary cause of hip revision — a factor determined by patient reports or patients returning to their surgeons. If no contact could be made to determine if a revision had occurred, the patient’s data were excluded from the study. Data examined included age, gender, labral treatment, microfracture of chondral surfaces and rehabilitation protocol.

The investigators followed more than 1,200 hip cases. Fifty-seven (4.5%) of hips required revision arthroscopy, 153 hips underwent labral debridement and 1,196 underwent labral repair. Six of the 153 labral debridements had adhesions, while 57 hips of the 1,196 hips that underwent labral repair were found to have adhesions — numbers which indicate no difference in adhesion prevalence between labral debridements and labral repairs.

Willimon reported that his group also discovered that 5% of patients who did not undergo microfracture were found to have adhesions, while 3% of those who underwent microfracture had adhesions. Certain patient-specific factors also played a part, he added.

“In our results, we found that age between the adhesion and non-adhesion group was statistically significant,” Willimon said.

Rehabilitation

The hip rehabilitation program used in the study was modified to include hip circumduction in November 2008. Willimon noted that 1,067 hips did not undergo circumduction and 291 hips underwent these exercises. Four cases in the circumduction group demonstrated adhesions, while compared to 61 in non-circumduction group — leading to a 4.4 times higher risk for adhesions among the non-circumduction group.

“This study has identified both patient- and rehabilitation-specific factors that contribute to an increased risk of adhesion formation,” Willimon concluded. “We feel strongly that circumduction exercises play a critical role in minimizing the risk of adhesion formation. Thorough analysis … revealed that rehabilitation factors, patient characteristics and operative techniques may play a role in adhesion formation following hip arthroscopy.” – by Robert Press

Reference:

Willimon SC, Philippon MJ, Briggs KK. Risk factors for adhesions following hip arthroscopy. Paper SS-39. Presented at the 2011 Annual Meeting of the Arthroscopy Association of North America. April 14-16. San Francisco.

S. Clifton Willimon, MD, can be reached at Children’s Orthopaedics of Atlanta, 5445 Meridian Mark Road, Suite 250 Atlanta, GA 30342; email: cliff.willimon@gmail.com

Disclosure: Willimon has no relevant financial disclosures.

The authors do an excellent job of statistically dissecting their experience with adhesions following hip arthroscopy. They have some unexpected observations that a number of intuitively suspected risk factors were actually not a problem. They noted the introduction of their circumduction exercises reduced the incidence of adhesions, but this, compared to a historical control group introduces the risk that other factors, such as improved surgical technique, may represent confounding variables.

It seems all patients undergoing repeat arthroscopy were found to have adhesions. Thus, is it possible that these types of adhesions might simply be present among some patients who did not require repeat arthroscopy? Also, did the authors have any data or impressions about whether removing the adhesions improved their patients’ results? This information would be necessary in order to support their postulation that the adhesions were the source of pain.

Lastly, it appears patients who were not able to be contacted were excluded from their data. This number of lost to follow-up is important in order to better appreciate the validity of their observations.

— J.W. Thomas Byrd, MD
Session moderator
Disclosure: Byrd is a consultant to Smith & Nephew and A2 Surgical,
receives research support from Smith & Nephew
and holds stock in A2 Surgical