Management of Isthmic Spondylolisthesis with Endoscopic Foraminoplasty

 

Martin T.N. Knight, FRCS *^Ä, Anukul Goswami, MS, MCh(Orth),DNB*,

 

*The Spinal Foundation, Arbury Centre, Manchester Road, Rochdale OL11 4LX, U.K.

*University of Central Lancashire, Preston PR1 2HE, U.K.

^{ÄUniversity of Manchester, Oxford Road, Manchester, UK}

 

Study Design. Prospective evaluation of Endoscopic Foraminoplasty performed on 30 consecutive patients with isthmic Spondylolisthesis followed for a minimum of 2 years.

Objectives. - To assess the efficacy of endoscopic aware state pain source definition of the symptomatic level.

- To assess endoscopic foraminal decompression and mobilisation of the exiting and transiting nerves, ablation of osteophytes, impinging pars and discectomy as a means of treatment.

Methods. Endoscopic Laser Foraminoplasty was performed on 16 males and 14 females with an average age of 42.7 years (36-72 years) followed for an average period of 34 months (28-46 months). The average preoperative duration of symptoms was 6.1 years (3 - 9 years).

Results. 100% cohort integrity was maintained at the final follow up.  Results were analysed using the percentage change in Oswestry Disability Scores and in Visual Analogue Pain scores. Using a percentage change in Oswestry Disability Score of 50 or more to determine good and excellent outcomes, 77% (23 out of 30) exceeded this value with 5 (17%) having 100% benefit from the procedure.   The adjacent level was causal in 4/30 patients.

Conclusion. Spinal probing and discography provides a minimalist means of identifying the symptomatic intervertebral segment.  Endoscopic Laser Foraminoplasty (ELF) provides a minimalist means of exploring the extraforaminal zone, the isthmic defect, the foramen and its contents, and the epidural space. Performed in the aware state, it serves to identify and localise and discretely treat the source of pain generation.  ELF allows resection of impinging pars and defect together with decompression, discectomy, osteophytectomy, perineural neurolysis as a “day-case” procedure.  It reduces the need for open decompression and fusion and targets the symptomatic level effectively.

 

 

 

Diagram of potential pain sources and their accessibility by posterolateral endoscopic laser foraminoplasty