The progressive painful and disabling predicament of patients with severe osteoarthritis awaiting a total hip or knee arthroplasty (THA/TKA) results in a decline in muscle mass, strength and function also known as Sarcopenia. We conducted a cross-sectional, prospective study of patients on the waiting-list for a THA/TKA in the South Australian public healthcare system and compared the findings to healthy participants and patients newly referred from their general practitioners. Participants with a history of joint replacements, pacemakers and cancers were excluded from this study. Outcomes of this study included (i) sarcopenia screening (SARC-F ≥4); (ii) sarcopenia, defined as low muscle strength (hand grip strength M<27kg; F<16kg), low muscle quality (skeletal muscle index M<27%, F<22.1%) and low physical performance (short physical performance battery ≤8). Additional outcomes include descriptions of the recruitment feasibility, randomisation and suitability of the assessment tools. 29 healthy controls were recruited; following screening, 83% (24/29) met the inclusion criteria and 75% (18/24) were assessed. 42 newly referred patients were recruited; following screening, 67% (30/45) met the inclusion criteria and 63% (19/30) were assessed. 68 waiting list patients were recruited; following recruitment, 24% (16/68) met the inclusion criteria and 75% (12/16) were assessed. Preliminary data shows increasing waiting time is associated with higher SARC-F scores, lower hand grip strength and lower muscle quality. As a pilot study, preliminary data demonstrate that: (1) study subjects’ willingness to participate will enable a larger study to be conducted to establish the prevalence of sarcopenia and the diagnostic cut-off points for this patient group. (2) SARC-F is a suitable tool to screen for sarcopenia. (3) There is a positive correlation between waiting time for a THA/TKA and sarcopenia.
In relation to the conduct of this study, one or more of the authors is in receipt of a research grant from a non-commercial source.
The primary source for the blood supply of the head of the femur is the deep branch of the medial femoral circumflex artery (MFCA). In posterior approaches to the hip and pelvis the short external rotators are often divided. This can damage the deep branch and interfere with perfusion of the head. We describe the anatomy of the MFCA and its branches based on dissections of 24 cadaver hips after injection of neoprene-latex into the femoral or internal iliac arteries. The course of the deep branch of the MFCA was constant in its extracapsular segment. In all cases there was a trochanteric branch at the proximal border of quadratus femoris spreading on to the lateral aspect of the greater trochanter. This branch marks the level of the tendon of obturator externus, which is crossed posteriorly by the deep branch of the MFCA. As the deep branch travels superiorly, it crosses anterior to the conjoint tendon of gemellus inferior, obturator internus and gemellus superior. It then perforates the joint capsule at the level of gemellus superior. In its intracapsular segment it runs along the posterosuperior aspect of the neck of the femur dividing into two to four subsynovial retinacular vessels. We demonstrated that obturator externus protected the deep branch of the MFCA from being disrupted or stretched during dislocation of the hip in any direction after serial release of all other soft-tissue attachments of the proximal femur, including a complete circumferential capsulotomy. Precise knowledge of the extracapsular anatomy of the MFCA and its surrounding structures will help to avoid iatrogenic avascular necrosis of the head of the femur in reconstructive surgery of the hip and fixation of acetabular fractures through the posterior approach.