The Histological In-growth of The Histological In-growth of Soft Tissue into the Nottingham Soft Tissue into the Nottingham Hood ProsthesisHood Prosthesis

P Durani, I-H Jeon, TA McCulloch, A McLeod, WA Wallace

Nottingham Shoulder & Elbow Unit

Nottingham City Hospital

A polyester soft tissue reinforcement device

Used as reinforcement for patients with shoulder arthroplasties complicated by medium or large tears of the rotator cuff (RCTs)

Introduced in 1987, number of modifications made since then

Used on a named patient basis for 10 years on humanitarian grounds – alternative option for patients with massive RCTs

30 Nottingham Hoods inserted over the past 10 years

The Nottingham HoodThe Nottingham Hood

AimAim

Investigate the histological changes associated with the Nottingham Hood:

• Amount of fibrous tissue ingrowth• Level of inflammatory reaction

How do the histological changes vary with length of time from implantation ?

The Nottingham HoodEmbroidered polyester – can be cut without fraying

AnteriorFlange

MiddleFlange

PosteriorFlange

Holes for Hooks on stem

PolyethyleneGlenoid

Humeral Stem

Posterior FlangeSutured

MethodMethod

4 patients who have had shoulder prostheses with a Hood inserted for associated massive RCTs

Re-operations for various reasons

Excised material subject to histological analysis

Excised biopsy material obtained at:– 6 weeks, 5 months, 9 months and 14 years

Routine and polarised light microscopy has been used in all cases

Results : Patient 1 Results : Patient 1 87 yr old lady with severe arthritis; bilateral TSRs –

satisfactory left TSR but unstable right TSR.

Suffered CVA, left sided hemi-plegia – became dependent on Right shoulder for ADLs

Right TSR revision: glenoid component removed, glenoplasty, humeral head relocated with a Nottingham Hood to retain it in position

Operated shoulder re-dislocated while nursing staff moving patient in bed

Re-op: glenoid reconstructed, Hood removed

Polarised Light Microscopy: Patient 1 (at 6 weeks)Polarised Light Microscopy: Patient 1 (at 6 weeks)

Polyester material

Thrombus

Polyester material Red blood cells

Fibrin

High Power Microscopy : Patient 1 (at 6 weeks)

Results : Patient 2 Results : Patient 2

76 yr old lady with bilateral lower limb amputations after an accident at 17 years old

Severe arthritis of weight-bearing left shoulder : left TSR carried out

Several revisions: stabilised anteriorly with reinforcement from Nottingham Hood

Visualised at a re-operation 5 months later, and biopsy taken

Intra-Op Macroscopic Features (at 5 months)Intra-Op Macroscopic Features (at 5 months)

Nottingham Hood In Situ

Anterior flange of Hood

Polarised Light Microscopy: Patient 2 (at 5 months)Polarised Light Microscopy: Patient 2 (at 5 months)

Polyester Material

Fibrous tissue

Polyester material

Fibrin

Collagen

High Power Microscopy : Patient 2 (at 5 months)

Results: Patient 3Results: Patient 3

73 year old man with severe arthritis, a complete rotator cuff tear and anterior dislocation of Left shoulder

Nottingham Hood inserted with a Left Neer prosthesis in 1989

Revision operation 9 months later due to loose glenoid. Nottingham Hood removed at this time, and sent for histology.

Routine Microscopy: Patient 3 (after 9 months)Routine Microscopy: Patient 3 (after 9 months)

4 strands of polyester material

Fibrous tissue

High Power: fibrous tissue ingrowth of polyester strands

Results: Patient 4Results: Patient 4

66 yr old with bilateral shoulder arthritis; right shoulder hemi-arthroplasty in 1988

Co-existent massive RCT augmented with Nottingham Hood (early version)

Continued problems, Right revision hemi-arthroplasty in 2002

Nottingham Hood (early version) removed and analysed; replaced with Nottingham Hood (latest version)

Polarised Light Microscopy: Patient 4 (after 14 years)Polarised Light Microscopy: Patient 4 (after 14 years)

Polyester material

Surrounding Collagen

Polyester fibresFibrin

Fascia-likeCollagen

High Power Microscopy: Patient 4 (at 14 years)

Masson-Trichome Stain : Patient 4 (after 14 years)Masson-Trichome Stain : Patient 4 (after 14 years)

Polyester

Collagen

Summary of ResultsSummary of Results

Case No.

Age

(yrs)

Gender Time at Biopsy

Histology

1 87 F 6 weeks Fibrin insinuated between bundles of meshwork. Thrombus like formation. No true ingrowth.

2 76 F 5 months Granulation and fibrous tissue. FB giant cell response.

3 73 M 9 months Strands of polyester material surrounded by new fibrous tissue ingrowth.

4 66 M 14 years Foreign material arranged as parallel fibres within tissue. Invested with layer of fascia-like collagen. Associated FB giant cell reaction.

ConclusionConclusion

Early organisational response to the insertion of the new material

Long-term incorporation into host tissues by fibrosis and scarring

Small fibrin and foreign body response lingers on

Suggests long-term implantation of polyester as reinforcement of RCTs is not associated with serious biological problems