Electronic Letters to:

Hip: M. Cashin, H. Uhthoff, M. O’Neill, and P. E. Beaulé Embryology of the acetabular labral-chondral complex J Bone Joint Surg Br 2008; 90-B: 1019-1024 [Abstract] [Full text] [PDF]

eLetters: Submit a response to this article

Electronic letters published:

Embryology of the acetabular labral-chondral complex

Russell C. Fritz   (5 March 2009)

Authors' reply:

Paul Beaule, Megan Cashin, Hans Uhthoff, Paul E. Beaule   (20 February 2009)

Embryology of the acetabular labral-chondral complex

Alexander L Dodds   (17 December 2008)

Embryology of the acetabular labral-chondral complex 5 March 2009
Russell C. Fritz, radiologist National Orthopedic Imaging Associates Send letter to journal: Re: Embryology of the acetabular labral-chondral complex rfritzmd{at}aol.com Russell C. Fritz	Sir, I read this paper with interest. The description of the posterior labrum is in line with previous anatomical descriptions. However, the description of the anterior labrum found in the sagittal slides of the 11 foetal specimens selected for this paper seems at odds with all other previous anatomical descriptions of the anterior labrum. A loosely attached meniscoid anterior labrum with a free edge in all foetal specimens does not seem plausible based on comparison with the previously published gross descriptions of cadaver specimens. The anatomical work of Byers, cited in this paper, clearly shows progressive detachment of the labrum from the articular cartilage of the acetabulum that becomes more common with age but does not exist at birth. The description of the anterior labrum also seems at odds with published experience and our clinical experience with arthroscopy and MR imaging of the anterior labrum in children. Clearly, most childen have an anterior labrum that is firmly attached to the acetabular cartilage. Since the gross specimens in this study were not available for inspection and review, caution is warranted regarding the authors' description of the foetal anterior labrum. The description of the anterior labrum in the paper seems more like a description of the transverse ligament. Perhaps the foetal position of the specimens with rotation of the pelvis has resulted in sagittal slides that depict the transverse ligament and superior labrum in cross section rather than the anterior and posterior labrum in cross section. I look forward to future work in which there is a careful description of the gross anatomy of the foetal labrum with marking of the orientation of the specimens prior to the histology. Until then, I think that the data is quite interesting but controversial. R.C. Fritz, Radiologist, National Orthopedic Imaging Associates, USA.
Authors' reply: 20 February 2009
Paul Beaule, Head, Adult Reconstruction University of Ottawa, Megan Cashin, Hans Uhthoff, Paul E. Beaule Send letter to journal: Re: Authors' reply: pbeaule{at}ottawahospital.on.ca Paul Beaule, et al.	Sir, In response to Mr Dodds' letter, we have answered the questions regarding the methodology of our study. Each fetal specimen was from a different hip. None of these hips was bilateral, i.e. from the same specimen. The ages of the fetal specimens ranged from eight weeks to full term. One specimen of each of the following ages was analysed: 8 to 9.5 weeks, 10 to 11 weeks, 12 weeks, 12.5 to 13 weeks, 13 weeks, 14 weeks, 15 to 16 weeks, 16.5 weeks, 17 weeks, 19 to 20.5 weeks and 36 weeks. We observed skeletal malformations in approximately 10% of over 400 specimens in our collection. However, skeletal malformations were not observed in any of the specimens used in the current study. Each specimen was independently analysed by the second author. Finally, the specimens were collected between 1960 and 1973, during which time ethical committees did not exist in Canada. Provincial law required that all embryologic and fetal specimens were to be kept by the pathology department. This law dictated that research could not be conducted on these specimens. After 1973, research was permitted. M. CASHIN, MD, Resident, H. UHTHOFF, MD, FRCS C, Professor Emeritus, P.E. BEAULE, MD, FRCS C, Associate Professor The Ottawa Hospital, Ottawa, Ontario, Canada.
Embryology of the acetabular labral-chondral complex 17 December 2008
Alexander L Dodds, Registrar Trauma and Orthopaedic Surgery Welsh Higher Surgical Training Programme for Trauma and Orthopedic Surgery, UK Send letter to journal: Re: Embryology of the acetabular labral-chondral complex DoddsAL{at}hotmail.com Alexander L Dodds	Sir, I read this paper with interest, and the associated online response from Messrs Bunn and Villar. However, I would like to highlight some points in the methodology which were not clear. The authors state that they "identified 11 specimens cut exactly in the sagittal plane". Was each of these specimens from a different hip? If so, were any of them bilateral specimens? The first author selected the specimens himself - did anyone else analyse them independently? The authors have not stated the exact ages of the different specimens used other than that there was a range from eight weeks to term. What were the exact embryological ages of the 11 specimens, and was any difference noted between them? The study used spontaneously aborted fetuses. These specimens will almost certainly have underlying pathology, and this could significantly affect the results when studying normal anatomy, limiting conclusions that can be drawn. Finally, given recent scandal in the UK regarding the storage and analysis of histopathological specimens, how was consent obtained by the authors for the use of the specimens and were any research or ethics committees consulted? A. L. Dodds, BSc MbBCh MRCS(Ed), Registrar, Wales Higher Surgical Training Programme for Trauma and Orthopaedics, Wrexham Maeloer Hospital, Wrexham, UK.