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Does the lumbar spine need to be supported to stabilize the pelvis during total hip arthroplasty in the lateral position?
The Journal of Arthroplasty Vol. 17 No. 3 2002
Does the Lumbar Spine Need to be Supported to Stabilize the Pelvis During Total Hip Arthroplasty in the Lateral Position? D. Prakash, FRCS (Orth),* R. King, FRCS,* and C. Hayes, BSc†
Abstract: Total hip arthroplasty is done commonly with the patient in the lateral position. It has been postulated that the lumbar spine may sag in this position because it forms a mobile link between the rigidly held thoracic spine and the sacrum and may cause the pelvis to tilt in the coronal plane, leading to malpositioning of the acetabular cup. To confirm this hypothesis, 10 consecutive patients seen in the preoperative assessment clinic had 2 anteroposterior radiographs taken in the lateral position. The area of exposure was from the lower thoracic spine to the sacrum. In the first radiograph, the lumbar spine was unsupported, and in the second, it was supported. The radiographs showed that the support did not make any significant difference to the position of the lumbar spine or to the position of the pelvis. Key words: arthroplasty, lumbar spine, acetabular cup, pelvic stability.
Patients and Methods
Total hip arthroplasties (THAs) commonly are performed with the patient in the lateral position. Rigid support of the pelvis is imperative to achieve correct orientation of the acetabular cup [1,2]. The usual method of stabilizing the pelvis in this position is to have anterior and posterior supports only. Because the lumbar spine is mobile, it was postulated that it might sag under its own weight, causing the pelvis to tilt in the coronal plane. If this were to occur undetected by the operating surgeon, it would lead to malpositioning of the acetabular cup intraoperatively. This study was undertaken to determine the validity of this postulate.
We reviewed 10 consecutive patients who attended the preoperative assessment clinic before their primary THAs. It was ensured that none of the patients had scoliosis, a paralytic disorder, or a previous THA. Two anteroposterior radiographs were taken of each patient in the lateral position. The radiographs exposed the spine from the lower thoracic region to the sacrum. In the first radiograph, no support was provided to the lumbar spine. Before the second radiograph was taken, a well-padded, custom-made instrument with adjustable height was placed between the lower ribs and the iliac crest and raised to support the lumbar spine. This lumbar support worked on a similar principle to a car jack, with the elevation being caused by the rotation of a central rod, which is threaded in opposite directions at its ends. A removable handle was used to adjust the height of this instrument when it had been put in place under the patient (Figs. 1 and 2). The second
From the *Queen’s Medical Centre, Nottingham; and †Derbyshire Royal Infirmary, Derby, United Kingdom. Submitted August 14, 2001; accepted September 6, 2001. No benefits or funds were received in support of the study. Reprint requests: D. Prakash, FRCS (Orth), 41 Westkirke Avenue, Grimsby, DN33 2HS UK. E-mail: Divya711@ hotmail.com. Copyright 2002, Elsevier Science (USA). All rights reserved. 0883-5403/02/1703-0007$35.00/0 doi:10.1054/arth.2002.30289
347
348 The Journal of Arthroplasty Vol. 17 No. 3 April 2002
Fig. 1. The lumbar support and the handle.
Fig. 2. The lumbar support can be raised to sufficient heights.
radiograph was taken exposing the same extent of the patient’s vertebra.
Result The radiographs did not show any significant sagging of the unsupported lumbar spine. Consequently, additional support of the spine did not make much difference to the position of the pelvis.
lumbar spine was not supported, practically it is not likely to occur to any significant extent.
Conclusion Additional support of the lumbar spine is not thought to be necessary for stabilizing the pelvis while THA is done with the patient in the lateral position.
References Discussion THA is a commonly performed operation, and it is performed commonly with the patient in the lateral decubitus position. Although much has been written about it, we could find no mention as to whether or not the mobility of the lumbar spine could lead to tilting of the pelvis in the coronal plane [1– 4]. As the quest for perfection continues in THA, any undetected movement of the pelvis during operation would not be acceptable to the surgeon. Our small study has shown that although there is the theoretical risk that the pelvis may tilt in the coronal plane if the
1. Harkess JW: Arthroplasty of hip. p. 296. In Canale ST (ed): Campbell’s operative orthopaedics, 9th ed. Mosby, St. Louis, 1998 2. Hardinge K: The hip. p. 184. In Evans DK (ed): Techniques in orthopaedic surgery. Blackwell Scientific Publications, Oxford, 1993 3. Hanssen AD: Anatomy and surgical approaches. p. 511. In Morrey BF (ed): Joint replacement arthroplasty. Churchill Livingstone, Rochester, NY, 1991 4. Hardinge K: Total hip replacement arthroplasty. p. 951. In Bentley G, Greer III RB (eds): Rob and Smith’s operative surgery, 4th ed. Butterworth-Heinemann, London, 1991
Does the Lumbar Spine Need to be Supported to Stabilize the Pelvis During Total Hip Arthroplasty in the Lateral Position? D. Prakash, FRCS (Orth),* R. King, FRCS,* and C. Hayes, BSc†
Abstract: Total hip arthroplasty is done commonly with the patient in the lateral position. It has been postulated that the lumbar spine may sag in this position because it forms a mobile link between the rigidly held thoracic spine and the sacrum and may cause the pelvis to tilt in the coronal plane, leading to malpositioning of the acetabular cup. To confirm this hypothesis, 10 consecutive patients seen in the preoperative assessment clinic had 2 anteroposterior radiographs taken in the lateral position. The area of exposure was from the lower thoracic spine to the sacrum. In the first radiograph, the lumbar spine was unsupported, and in the second, it was supported. The radiographs showed that the support did not make any significant difference to the position of the lumbar spine or to the position of the pelvis. Key words: arthroplasty, lumbar spine, acetabular cup, pelvic stability.
Patients and Methods
Total hip arthroplasties (THAs) commonly are performed with the patient in the lateral position. Rigid support of the pelvis is imperative to achieve correct orientation of the acetabular cup [1,2]. The usual method of stabilizing the pelvis in this position is to have anterior and posterior supports only. Because the lumbar spine is mobile, it was postulated that it might sag under its own weight, causing the pelvis to tilt in the coronal plane. If this were to occur undetected by the operating surgeon, it would lead to malpositioning of the acetabular cup intraoperatively. This study was undertaken to determine the validity of this postulate.
We reviewed 10 consecutive patients who attended the preoperative assessment clinic before their primary THAs. It was ensured that none of the patients had scoliosis, a paralytic disorder, or a previous THA. Two anteroposterior radiographs were taken of each patient in the lateral position. The radiographs exposed the spine from the lower thoracic region to the sacrum. In the first radiograph, no support was provided to the lumbar spine. Before the second radiograph was taken, a well-padded, custom-made instrument with adjustable height was placed between the lower ribs and the iliac crest and raised to support the lumbar spine. This lumbar support worked on a similar principle to a car jack, with the elevation being caused by the rotation of a central rod, which is threaded in opposite directions at its ends. A removable handle was used to adjust the height of this instrument when it had been put in place under the patient (Figs. 1 and 2). The second
From the *Queen’s Medical Centre, Nottingham; and †Derbyshire Royal Infirmary, Derby, United Kingdom. Submitted August 14, 2001; accepted September 6, 2001. No benefits or funds were received in support of the study. Reprint requests: D. Prakash, FRCS (Orth), 41 Westkirke Avenue, Grimsby, DN33 2HS UK. E-mail: Divya711@ hotmail.com. Copyright 2002, Elsevier Science (USA). All rights reserved. 0883-5403/02/1703-0007$35.00/0 doi:10.1054/arth.2002.30289
347
348 The Journal of Arthroplasty Vol. 17 No. 3 April 2002
Fig. 1. The lumbar support and the handle.
Fig. 2. The lumbar support can be raised to sufficient heights.
radiograph was taken exposing the same extent of the patient’s vertebra.
Result The radiographs did not show any significant sagging of the unsupported lumbar spine. Consequently, additional support of the spine did not make much difference to the position of the pelvis.
lumbar spine was not supported, practically it is not likely to occur to any significant extent.
Conclusion Additional support of the lumbar spine is not thought to be necessary for stabilizing the pelvis while THA is done with the patient in the lateral position.
References Discussion THA is a commonly performed operation, and it is performed commonly with the patient in the lateral decubitus position. Although much has been written about it, we could find no mention as to whether or not the mobility of the lumbar spine could lead to tilting of the pelvis in the coronal plane [1– 4]. As the quest for perfection continues in THA, any undetected movement of the pelvis during operation would not be acceptable to the surgeon. Our small study has shown that although there is the theoretical risk that the pelvis may tilt in the coronal plane if the
1. Harkess JW: Arthroplasty of hip. p. 296. In Canale ST (ed): Campbell’s operative orthopaedics, 9th ed. Mosby, St. Louis, 1998 2. Hardinge K: The hip. p. 184. In Evans DK (ed): Techniques in orthopaedic surgery. Blackwell Scientific Publications, Oxford, 1993 3. Hanssen AD: Anatomy and surgical approaches. p. 511. In Morrey BF (ed): Joint replacement arthroplasty. Churchill Livingstone, Rochester, NY, 1991 4. Hardinge K: Total hip replacement arthroplasty. p. 951. In Bentley G, Greer III RB (eds): Rob and Smith’s operative surgery, 4th ed. Butterworth-Heinemann, London, 1991