The size and prevalence of bony hip morphology does not differ between football players with and without hip and/or groin pain: findings from the FORCe cohort

Key Points

1. The size and prevalence of cam morphology did not differ in male football players between hips with and without hip and/or groin pain.
2. Prevalence of pincer morphology was low, particularly in females.
3. Prevalence of acetabular dysplasia was very low.

BACKGROUND & OBJECTIVE

Hip and groin pain are common in athletes competing in the football codes, with impacts on participation, sports performance, and quality of life. The hip joint is recognized as a common source of nociception, with bony morphological features such as cam morphology, pincer morphology, and acetabular dysplasia variably linked with symptoms.

This study of sub-elite football (soccer and Australian Football) players reported on baseline measures of the femoroacetabular impingement and hip osteoarthritis cohort (FORCe). The study aimed to: (i) compare the size and prevalence of bony hip morphology separately in men and women; and (ii) determine the relationship between the size of bony hip morphology and hip and/or groin-related symptoms and pain.

Hip and groin pain are common in athletes competing in the football codes.

Bony morphology is unlikely to be the only reason for the development of hip pain.

METHODS

Sub-elite football players were recruited from soccer and Australian Football clubs. Imaging was performed on 184 players (290 hips; 20% women) with hip and/or groin pain and a positive FADIR test; and 55 asymptomatic players (110 hips; 25% women) with a negative FADIR test.

Supine AP pelvis and Dunn 45° radiographs were collected, and alpha angle and lateral-centre-edge-angle (LCEA) measured. Patient-rated outcome measures were also collected, including the International Hip Outcome Tool (iHOT33) and the Copenhagen Hip and Groin Outcome Score (HAGOS). The HAGOS consists of six subscales but only the ‘Pain’ and ‘Symptom’ scales were analyzed in this study, to assess the relationship of bony morphology with hip pain and symptoms.

RESULTS

A summary of the findings on bony hip morphology prevalence in those with and without hip/groin pain can be seen in Figure 1.

In the hips of male football players, the size and prevalence of morphological variations didn’t differ with the presence of pain. However, painful hips in women did on average have a slightly larger (5.9°) alpha angle compared to pain-free hips, but with uncertain clinical significance.

Prevalence of pincer morphology, particularly in women, was low in this cohort. In female football players, there was an association between greater LCEA (indicating greater acetabular coverage) and higher scores on the HAGOS Pain subscale, but not with the HAGOS Symptom subscale.

Rates of acetabular dysplasia in these football players was very low and did not allow for statistical analysis of the association with pain or symptoms.

LIMITATIONS

• An intra-articular source of nociception cannot be confirmed by a FADIR test, due to the low specificity of this test (1). Therefore, these findings reflect an association with symptom status, rather than a causal relationship with hip joint pathology or nociception.
• The two-dimensional radiographic protocol may have underestimated prevalence or size of bony variations.
• The low number of women in this study reduces confidence in correlations and prevalence predictions for the wider female community.

CLINICAL IMPLICATIONS

The overall conclusion from this study was that for this cohort of football players, the size and prevalence of bony hip morphological variants was similar for players with and without hip and/or groin pain. The clinical implication here is that bony morphology is unlikely to be the only reason for the development of hip pain, as bony variants are just as common in football players without pain as they are in those with pain. This means that we need to identify other drivers of hip pain which may well be modifiable and therefore potentially amenable to rehabilitation.

However, the findings of this study do not indicate that bony morphology is irrelevant, as previous research has determined that cam morphology (2) and acetabular dysplasia (3) both increase the risk of early osteoarthritis. The presence of particular bony morphological features may therefore influence specific approaches to load management and exercise prescription used with such patients.

+STUDY REFERENCE

Heerey J, Agricola R, Smith A, Kemp J, Pizzari T, King M, Lawrenson P, Scholes M and Crossley K (2020) The size and prevalence of bony hip morphology does not differ between football players with and without hip and/or groin pain: Findings from the FORCe cohort. Journal of Orthopaedic & Sports Physical Therapy, doi: 10.2519/jospt.2021.9622.

SUPPORTING REFERENCE

1. Reiman, M., Goode, A., Cook, C., Hölmich, P. and Thorborg, K., 2014. Diagnostic accuracy of clinical tests for the diagnosis of hip femoroacetabular impingement/labral tear: A systematic review with meta-analysis. British Journal of Sports Medicine, 49(12), pp.811-811.
2. van Klij, P., Heerey, J., Waarsing, J. and Agricola, R., 2018. The prevalence of cam and pincer morphology and its association with development of hip osteoarthritis. Journal of Orthopaedic & Sports Physical Therapy, 48(4), pp.230-238.
3. Agricola, R., Heijboer, M., Roze, R., Reijman, M., Bierma-Zeinstra, S., Verhaar, J., Weinans, H. and Waarsing, J., 2013. Pincer deformity does not lead to osteoarthritis of the hip whereas acetabular dysplasia does: acetabular coverage and development of osteoarthritis in a nationwide prospective cohort study (CHECK). Osteoarthritis and Cartilage, 21(10), pp.1514-1521.