Peroneal Nerve Palsy after shoulder surgery
Perioperative peripheral nerve injuries are a common and devastating complications of anesthesia and surgery. Peroneal nerve injury is a recognized perioperative complication of having surgery in the lithotomy position likely secondary to its superficial course (1). However, peroneal injuries have not been described as complications related to shoulder surgery in the sitting (beach-chair) position.
We report 6 cases of peroneal nerve palsy occurring after total shoulder replacement (TSR) and present a literature review of neurologic complications during shoulder surgery in the beach chair position.
We identified 6 cases of peroneal nerve palsy following TSR in sitting beach-chair position that occurred in a single institution between 2014 and 2017 after reviewing medical records of 156 patients operated by 2 surgeons. After obtaining approval from the Institutional Review Board, we reviewed medical records (Prism ®, GE Healthcare, UK) for patient- related risk factors, including age, gender, height, weight, BMI, spinal pathology, pre-existing peripheral neuropathy, and diabetes. We reviewed the anesthetic records (Comp Record, Phillips®, MA) and surgical reports for surgical and anesthetic related factors including anesthetic technique, medications administered, duration of the procedure, placement of blood pressure cuff or intravenous catheter on a lower extremity, fluid administration, estimated blood loss, need for blood transfusion, and sustained hypotension during the procedure. We selected specific patient and perioperative risk factors based on literature reviews on other types of nerve palsies and peroneal nerve injuries that occurred in other surgical settings. Sentinel cases were closely examined for complete postoperative course to determine the time of symptom onset, type of neurologic deficits, subsequent workup and interventions, and symptom resolution.
Of the 6 cases of peroneal nerve palsy following TSR performed in the beach-chair position, 5 procedures were performed by a single senior orthopedic surgeon and the sixth by an orthopedic surgeon who was trained under the senior surgeon. The surgeons share similar positioning demands, surgical technique and duration, and approaches to perioperative management.
Male predominance was significant in these identified cases with average BMI of 33.3 and average duration of surgery and anesthesia were 268 min and 382 min respectively(Table1). All cases were performed under general anesthesia after receiving continuous interscalene nerve blockade preoperatively (Table 2). The average amount of intravenous fluids received was 1.8 L and average estimated blood loss was 300 mL. None of the patients required a blood transfusion during their hospital stay. No blood pressure cuffs or intravenous catheters were placed on lower extremities. All the patients had a brief period of hypotension (defined as systolic blood pressure decrease by over 20% of baseline) that was treated with phenylephrine boluses during the initial transition from supine into sitting position.
Four patients were male and 5 had some pre-existing lumbar spinal pathology . All peroneal nerve palsies were identified on either postoperative day 0 in the recovery room or day 1 on the wards. They were described as lower extremity numbness or both numbness over the lateral aspect of lower leg and motor deficit. All of them completely resolved or significantly improved on day of discharge, which occurred between postoperative day 2 and 4. Five patients received imaging of the lumbar spine (3 MRI, a CT scan, and an X-ray) (Table 3). The imaging studies showed nonspecific degenerative changes of the lumbar spine without any significant pathology. Four patients were seen by a consultation service - 3 by neurology and 1 by orthopedic spine service. There was no correlation between the laterality of nerve palsy and the operative side of shoulder surgery.
Mechanisms for nerve injury can be complex and multifactorial. Possible etiologies include direct trauma, mechanical stretching, nerve ischemia due to tourniquet use, local anesthetic exposure and underlying patient conditions such as diabetes or rheumatoid arthritis. Beach-chair sitting position has been associated with numerous neurologic complications, most notably neurocognitive complications thought to be caused by cerebrovascular ischemia from hypotension resulting from the sitting position(2). Clinically apparent nerve palsy after reverse shoulder arthroplasty appears to be rare and tends to involve the musculocutaneous nerve with an incidence up to 1.4% and axillary nerve which is probably related to the amount by which the nerve is lengthened. The nerve palsy is transient and review of orthopedic literature advocates cautious lengthening of the arm for the surgery (3). Lateral femoral cutaneous nerve palsy has been reported especially in those with high BMI (4). Greater auricular nerve palsy has been reported due to the use of universal standard headrest (5).
Closed claim analysis has also demonstrated that nerve injury can occur even with optimal patient positioning and padding to areas that are at risk (6). In this retrospective case series, potential risk factors identified were male gender and probable preexisting spinal pathology which was discovered only after imaging was done post operatively. In the vulnerable patient with underlying neurological or spinal pathology, it is possible that specific intraoperative positioning demands that involves securing patients to the beach chair such as foam padding under knees or strapping across the thighs can be associated with increased mechanical pressure and subsequent compression of the nerve contributed to causing palsy(7).No nerve studies were done on these patients as the consult services did not recommend one.
Beach chair position is favorable from surgeon’s point as it provides excellent visualization of glenohumeral joint, but involves appropriate positioning with padding of legs, arms to prevent traction injury (8) as well as strapping across the thighs. Tilting of the operating table is common in these surgeries to optimize surgical exposure but we found no correlation between the side of the peroneal nerve palsy and the shoulder operated on, therefore making table or patient tilting an unlikely contributor.
Yoon et al reported that there was predominant left sided peroneal nerve palsy in liver transplant patients which was attributed to the prolonged compression of the nerve around the fibular head by the restraining device when the operating table was tilted to facilitate liver mobilization in conjunction with intermittent pneumatic compression device. They used extra gel padding between the intermittent pneumatic compression device and the restraining device to prevent the same (9).
Kim et al reported that when gel-pads under the knees were introduced to prevent contact between the peroneal nerve at the fibular head and the hard surface of the operating table during liver transplants, the reported incidence of 1.4%–13.3% of peroneal neuropathy actually increased (10).
Transient peroneal nerve palsy may occur after shoulder surgery in sitting position with incidence as high as 3% at our institution. The mechanism of neuropathy in this setting is unclear. Perioperative lower extremity neuropathies occur infrequently, and extensive anatomic and sensorimotor nerve testing of a large surgical population would be needed to accurately determine the timing of onset, the precise location, and the potential causes of these neuropathies(11).
Its occurrence should be anticipated and prevented with appropriate positioning of the lower extremities during surgery, especially in the presence of potential risk factors such as pre-existing lumbosacral pathology and prolonged operative time (11). Our cases suggest this complication can be managed conservatively with good results without the need for surgical interventions like transposition and grafting of nonconductive lesions.
1.Warner M.A., Martin J.T., Schroeder D.R., et al: Lower-extremity motor neuropathy associated with surgery performed on patients in a lithotomy position. Anesthesiology 1994; 81: pp. 6-12.
2. Salazar D1, Hazel A, Tauchen AJ, Sears BW, Marra G, Neurocognitive Deficits and Cerebral Desaturation During Shoulder Arthroscopy With Patient in Beach-Chair Position: A Review of the Current Literature. Am J Orthop .2016 Mar-Apr;45(3): E63-8.
3. Lädermann A, Lübbeke A, Mélis B, et al. Prevalence of neurologic lesions after total shoulder arthroplasty. J Bone Joint Surg [Am] 2011;93-A:1288–1293.
4. Ari J. Holtzman, M.D., Christopher D. Glezos, M.D Prevalence and Risk Factors for Lateral Femoral Cutaneous Nerve Palsy in the Beach Chair Position. Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 33, No 11 (November), 2017: pp 1958-1962.
5. LaPrade CM, Foad A. Greater auricular nerve palsy after arthroscopic anterior-inferior and posterior-inferior labral tear repair using beach-chair positioning and a standard universal headrest. Am J Orthop (Belle Mead NJ). 2015 Apr;44(4):188-91.
8. John D. Higgins, B.A. Rachel M. Frank, Shoulder Arthroscopy in the Beach Chair Position, Arthroscopy techniques. August 2017Volume 6, Issue 4, Pages e1153–e1158.
10. Kim GS, Yoon JS1, Kee R, Shin YH. Association between the use of gel pads under patients' knees and the incidence of peroneal neuropathy following liver transplantation. Singapore Med J. 2014 Aug;55(8):432-5.
11. Mark A. Warner, M.D.; David O. Warner, M.D.; C. Michel Harper, M.D.; Darrell R. Schroeder, M.S.; Lower Extremity Neuropathies Associated with Lithotomy Positions, Anesthesiology 10 2000, Vol.93, 938-942.