EBS: Foot drop from lumbar spondylosis and outcomes after decompressive surgery

Anthony ChauAug 2015

Background

• ED referral: 44M electrician with 1 week of severe right-sided L5 radiculopathy after lifting, and 3/5 weakness ankle DF

• ED CT demonstrates L4/5 posterolateral disc protrusion

PICO question (1)

• P: adults with foot drop secondary to degenerative lumbar disc disease

• I: decompressive surgery• C: nil• O: improvement in neurological function

QUESTION:“What is the outcome of and how urgent is decompressive

surgery for patients with foot drop secondary to degenerative lumbar spondylosis”

Search Criteria

• Incl: RCTs, case series– Due to lumbar disc disease

• Excl: reviews, case reports– Foot drop from other surgical causes: e.g.

common peroneal nerve entrapment– Foot drop due to all medical causes

Strategy - Sources

• Databases– Medline (via OVID)– Cochrane CENTRAL

• Hand searching – Scopus bibliographies/ citation history check– Google screening

MeSH terms

CENTRAL database

Medline (1)

Medline (2)

Medline (3)

Medline (4)

PRISMA flow chartMedline 28 articlesCENTRAL 0 articles

Google 1 articleScopus cross reference 7 articles

36 abstracts reviewed

13 full text articles retrieved

Excluded: 23- Irrelevant: 22- Review article: 1

Excluded: 2-Irrelevant : 2

11 articles for qualitative review

0 articles for quantitative review

Results – Study summaries (2)Study, country Study Design Definition

foot dropIntervention

Knutsson 1962, Sweden Retrospective DF weakness Discectomy

Jonsson 1995, Sweden Prospective MRS<3/5 Discectomy; laminectomy

Guigui 1998France

Retrospective MRS <4/5 Decompression

Girardi 2002 USA Retrospective MRS <5/5 Microdiscectomy (HNP); laminectomy +/- fusion

Postacchini 2002, Italy Prospective MRS <5/5 Microdiscectomy

Aono 2007, Japan Retrospective MRS <3/5 Microdiscectomy; laminectomy

Ghahreman 2009, Australia

Retrospective MRS <3/5 Decompression

Iizuka 2009, Japan Retrospective MRS <4/5 Microdiscectomy (HNP); laminectomy +/- PLF (SCS)

Bhargava 2012, UK Retrospective MRS <4/5 Microdiscectomy; laminectomy

Liu 2013, China Retrospective MRS <4/5 Microdiscectomy; laminectomy

Aono 2014, Japan Retrospective MRS <3/5 Microdiscectomy; laminectomy

Results – Study summaries (1)Study, country

n Age (y)

Aetiology Duration preop Sx Mean (range)

F/u Postop Improve

Positive association for Improvement

No association for Improvement

Knutsson 1962 Sweden

123

NS HNP 1-10 mo 1 yr 74% Preop weakness -

Jonson 1995 Sweden

35 50 HNP, spinal canal stenosis

Not specified 24 mo 63% Aetiology HNP> lateral stenosis> central canal stenosis

Duration of preop sx, age

Guigui 1998 France

50 65 HNP, spinal canal stenosis

<3, 3-6, 6-12 >12 wks

38 80% Duration of preop sx, aetiology HNP> canal stenosis

Preop weakness, cauda equina, spondylolisthesis

Girardi 2002 USA

55 47 HNP, spinal canal stenosis

110 days (6 days – 2.5 yrs)

36 98% - Duration of preop sx, preop weakness, aetiology, age

Postacchini 2002, Italy

116

49 HNP Not specified >6 mo 84% Inverse relation to duration of preop sx and preop weakness

Age

Aono 2007Japan

46 57 HNP, spinal canal stenosis

97 days 2-9 yrs

61% Duration of preop sx, preop weakness

-

Ghahreman 2009 Australia

34 51 HNP, spinal canal stenosis

14 days (1-180)

24 mo 27% complete

Preop weakness, age Duration of preop sx

Iizuka 2009 Japan

28 55 HNP, spinal canal stenosis

3 wks (1-52) 6-60 mo

54% Preop weakness (p<0.05), and HNP aetiology (p=0.011)

Duration of preop sx

Bhargava 2012 UK

26 48 HNP, spinal canal stenosis

<4, 4-6, >6 wks >6 mo 88% Duration of preop sx (p=0.019) -

Liu 2013 China

135

55 HNP, spinal canal stenosis

186 days (14-365)

2-3 yrs

84% Duration of preop sx (p=0.04), preop weakness (p=0.003) and age (p=0.03)

-

Aono 2014 Japan

21 52 Painless foot drop from HNP, spinal canal stenosis

129 days (15-700)

2-9 yrs

65% Duration of preop sx main prognostic factor (p=0.03). No diff HNP for SCS, radiculopathy vs CES, single vs multilevel

-

Weaknesses of search strategy

• Only looked for foot drop studies– May have missed large lumbar surgery studies

with subset analysis of patients with foot drop• Only case series identified in the literature – Heterogeneous population and interventions

Conclusions

• Disagreement in the literature regarding the urgency of surgical decompression in lumbar spondylotic foot drop– But very heterogeneous population– Probably ‘case by case’ decision-making required

• Some form of neurological improvement can be expected in the majority of cases