Tandem keyhole foraminotomy in the treatment of cervical radiculopathy: retrospective review of 35 cases

Abstract

Background: There has been no report regarding the results of two-level keyhole foraminotomy. The purpose of this study was to detail clinical outcomes following consecutive two-level cervical foraminotomy (tandem keyhole foraminotomy (TKF)) in patients with radiculopathy.

Methods: The authors conducted a retrospective review of 35 cases involving patients treated by a single surgeon using TKF. Clinical symptoms, data of physical examinations, pathology and clinical outcomes were detailed and discussed about this surgical method.

Results: Patients consisted of cervical disc herniation (CDH) (19/35), cervical spondylotic radiculopathy (CSR) (13/35), and cervical spondylotic amyotrophy (CSA) (3/35). TKF was performed from C3 to C5 in 2 patients (6%), from C4 to C6 in 7 patients (20%), from C5 to C7 in 23 patients (66%), and from C6 to T1 in 3 patients (8%). The mean operative duration was 99.2 min (range, 72 to 168 min). The mean estimated blood loss was 55.8 g (range, 0 to 200 g). Radicular pain was relieved within 3 months in 88% (29/32) and in 97% (31/32) at final follow-up. Resolution of muscle weakness was recognized within 6 months after operation in all CSA cases. Sixty-six percent of patients showed a greater than 20% deficit in grip weakness on the affected side compared with the normal side. After pain was relieved, grip strength improved by more than 15%.

Conclusions: TKF is a safe and highly effective procedure for patients with cervical radiculopathy and does not require invasive preoperative examinations. Further investigation is required to determine the effects of consecutive facetectomy.

Figure 1

Retraction system and TKF. (A) METRx™ Quadrant.(B) Tandem keyhole foraminotomy as seen through the Quadrant.

Figure 2

Postoperative 3D CT view. Tandem keyhole foraminotomy was performed in C5/6/7. Half of the facet joints were preserved. The lateral border of vertebral body was recognized through the decompressed hole.

Figure 3

Scheme of the operative site. N, nerve root; P, pedicle; H, herniated disc or bony spur. Left: posterior view of the operating field. Decompression must be done until both proximal and distal pedicles were confirmed. Right: nerve root can be shifted posteriorly after appropriate decompression. Herniated discs or bony spur need not to be removed.

Figure 4

Grip strength (kg) of pre- and post-operation shown in symptomatic and non-symptomatic side. *P < 0.01: pre-nonsymptomatic vs pre-symptomatic. **P < 0.01: post-nonsymptomatic vs post-symptomatic. ***P < 0.01: pre-symptomatic and post-symptomatic.