Parastomal Hernia Repair

No dedicated page existed for this topic before this ingest — Intestinal Stomas only carried the overall incidence range (0–40%) as a line in its complications table. Content below is from a textbook reference chapter (ASCRS Ch55 - Abdominal Wall Reconstruction and Parastomal Hernia Repair), not primary literature. Despite the chapter's title, its content is almost entirely about parastomal hernia specifically — the "abdominal wall reconstruction" techniques described (retromuscular repair, transversus abdominis release/TAR) appear here only in the context of repairing a parastomal defect, not as a general AWR topic.

Parastomal hernia (PSH) is defined as an incisional hernia at the site of an ostomy — one of the most common complications of stoma creation (see Intestinal Stomas). Reported rates vary widely with stoma type, patient characteristics, follow-up duration, and diagnostic definition, but are generally ~30% by 1 year and ~40% by 2 years, exceeding 50% with longer follow-up. Some authors consider PSH development essentially inevitable given sufficiently long follow-up. Both ASCRS and the Association of Coloproctology of Great Britain and Ireland have named PSH prevention/repair a top research priority.

Incidence by stoma type

Stoma type	PSH incidence
End colostomy	4–48%
Ileal conduit	17%
End ileostomy	2–28%
Loop colostomy	0–31%
Loop ileostomy	0–6%

End colostomies carry the highest incidence; loop ileostomies the lowest (likely reflecting their transient presence). An enlarged trephine at stoma creation is associated with PSH formation — the surgeon must balance minimizing the fascial defect against avoiding ischemia to the traversing bowel (see Intestinal Stomas's technical-creation section).

Risk factors and diagnosis

Advanced age, diabetes, surgical site infection, malnutrition, immunosuppression, malignancy, and emergent presentation have all been implicated, but obesity and waist circumference carry the strongest evidence-supported association. A Swedish national registry of >6,300 permanent colostomy patients identified BMI >30 kg/m² as the only independent risk factor for PSH development; a waist circumference >100 cm carries a 75% probability of developing PSH. This makes preoperative weight loss a genuinely high-value intervention where feasible.

PSH incidence plateaus after the first two postoperative years in large prospective series, though one 202-patient French cohort found a median time-to-presentation of 18 months with a range up to 27 years — underscoring the value of long-term (≥1 year) stoma follow-up. A practical clinical definition (Israelsson): "any palpable defect or bulge adjacent to the stoma detected when the patient is supine with legs elevated or while coughing or straining when the patient is erect" — though inter-observer reliability among staff surgeons is worse than one would expect. Self-reported diagnosis appears to be a reasonably good indicator of clinically significant PSH: in one cohort, 76% of self-identified PSH patients had symptoms and 56% had undergone repair. CT imaging is useful for operative planning (concomitant incisional hernia, obstruction, defect size for re-siting decisions) but has real limitations: it can overestimate PSH by misinterpreting redundant subcutaneous bowel, and a standard supine acquisition may under-detect a bulge that would be evident standing/prone or with Valsalva. Patient self-assessed symptoms correlate with the need for operative intervention more reliably than imaging.

Symptoms and complications

Symptom/complication	Rate
Pain	35%
Appliance difficulty	28%
Leakage	27%
Irrigation difficulty	24%
Skin irritation	22%
Prolapse	18%
Obstruction	15%
Hemorrhage	2%

Classification

Several classification schemes exist, none validated or widely adopted: Rubin and Bailey ("true" parastomal hernia, intrastomal hernia, subcutaneous prolapse, pseudohernia), Devlin (interstitial, subcutaneous, intrastomal, peristomal), and Gil/Szczepkowski/Moreno-Matias systems. The European Hernia Society (EHS, 2014) classification is the most pragmatic, incorporating the two variables that most affect surgical decision-making — defect size and the presence of a concomitant incisional hernia:

EHS class	Defect size	Concomitant incisional hernia
I	<5 cm	No
II	<5 cm	Yes
III	>5 cm	No
IV	>5 cm	Yes

Operative indications

A selective approach to repair is warranted given high recurrence rates with surgery. Only ~22% of stomas are reversible at the time of hernia repair (Abdominal Core Health Quality Collaborative data), so in the vast majority of cases the surgeon must deal with the traversing bowel again rather than simplifying to a standard incisional hernia repair. No repair technique is highly durable — recurrence can exceed 50% even with mesh reinforcement and long-term follow-up, and each subsequent repair with prosthetic reinforcement tends to become progressively more complex, with reported complication rates >50% and reoperation rates of 12%. Given this, up to 70% of patients living with a PSH do not pursue an operation — a preference often shared by the surgeon, and there is no strong evidence describing the consequences of watchful waiting (some surgeons report safe non-operative practices anecdotally). A standardized quality-of-life instrument for this population (the PROPHER study, European Society of Coloproctology) is in development.

Repair should generally be offered to: patients with a history of PSH complications (most commonly bowel obstruction or prolapse), or symptoms causing significant QoL limitation. An honest discussion of realistic recurrence risk and the optimization steps below should precede any elective repair decision.

Preoperative optimization

Parameter	Target
BMI	<35–40 kg/m²
Smoking cessation	≥4 weeks
Hemoglobin A1c	<7–8%
Stoma marking	All patients
Bowel prep	Not indicated

Most experts agree surgery should be offered at BMI <30 kg/m² and considered prohibitive above 50 kg/m²; the 30–50 range lacks strong prospective evidence, though retrospective AHSQC data on incisional hernias generally shows progressively lower wound morbidity with lower BMI without a clear safe cutoff. Smoking cessation (≥4 weeks) and glycemic control (HbA1c <7–8%) have similar wound-morbidity correlations. Preoperative stoma marking should be performed even when re-siting isn't planned, given documented benefits to postoperative complications, QoL, and independence (see Intestinal Stomas). Routine bowel prep is not evidence-supported — it can increase watery stool leakage during bowel manipulation, and ACHQC data found no wound-morbidity benefit, with a possible increased need for procedural intervention in contaminated cases. Emergent/temporizing maneuvers (stoma relocation without mesh, requiring a midline laparotomy) should be reserved for patients in extremis or unoptimized patients needing urgent repair (typically for obstruction) — recurrence rates as high as 86%, plus up to 52% risk of a new midline or prior-stoma-site hernia; risk compounds further with ipsilateral or multiple re-siting attempts.

Repair techniques

No randomized trials compare parastomal hernia repair techniques with mesh reinforcement — all evidence below is from case series and pooled/meta-analyses.

Primary repair

Largely abandoned given recurrence rates up to 80%. Stoma relocation without mesh reinforcement (also typically requiring a midline laparotomy) performs similarly poorly (see the emergent-maneuver figures above).

Onlay mesh repair

Extraperitoneal dissection (incision ≥10 cm from the stoma to avoid appliance interaction) through the anterior rectus sheath/external oblique aponeurosis/hernia sac circumferentially, fascial approximation toward a two-finger-breadth aperture, then onlay polypropylene mesh — keyhole slit if the stoma is left in situ, cruciate incision if mobilized. Avoids laparotomy (useful in high-risk patients with small/medium defects) but does not address a concomitant incisional hernia, and skin flap elevation risks wound ischemia/seroma (manageable with closed suction drains).

Series	n	Technique	Follow-up (mo)	Recurrence
Ho	15	Keyhole, polypropylene	15 (mean)	7%
De Ruiter	46	Cruciate PP + PP ring	51 (mean)	15% (26% required mesh removal)
Steele ("stove pipe hat")	58	Cruciate PP + circumferential bowel mesh	51 (mean)	26%
Warwick	30	Keyhole, porcine dermis biologic	36 (median)	90%

Pooled analysis (Hansson 2012, 149 patients, ≥1 year follow-up, median 3 years): 19% overall recurrence, with reassuringly low surgical site infection (2%) and mesh infection (2.6%) rates, tempering theoretical concerns about devascularized skin flaps. The Warwick biologic-mesh result is a notable outlier warning against keyhole biologic mesh as a polypropylene substitute in this position.

Open intraperitoneal mesh repair

Following parastomal defect closure, mesh (≥5 cm overlap) is placed intraperitoneally in either a keyhole/cruciate orientation (bowel exits through a mesh slit) or the Sugarbaker orientation (bowel lateralized as it exits the peritoneal cavity, mesh placed directly over the hernia site, bowel draped between abdominal wall and prosthetic — creating a valve effect with increased abdominal pressure). Sugarbaker's original description (7 patients) had zero recurrences at 5-year average follow-up. Sugarbaker allows more bowel-prosthetic interface (theoretical erosion concern) but avoids the mesh-shrinkage/orifice-enlargement failure mode that affects keyhole/cruciate repairs. Contemporary repairs use anti-adhesive barrier-coated synthetic mesh or ePTFE rather than the original uncoated polypropylene.

Series	n	Technique	Follow-up (mo)	Recurrence
Byers	9	Keyhole, polypropylene	13 (mean)	0%
Morris-Stiff	7	Keyhole, polypropylene	78 (mean)	29%
Hofstetter	13	Keyhole, ePTFE	NR	0%
Van Sprundel	16	Keyhole, ePTFE	28 (mean)	6%
Stelzner	20	Sugarbaker, ePTFE	42 (mean)	15%

Pooled analysis (Al Shakarchi/Williams): 65 patients, 9% recurrence at 38-month mean follow-up, 3% SSI, 1 mesh infection.

Laparoscopic intraperitoneal mesh repair

The rapid adoption of the laparoscopic approach explains the relative paucity of open intraperitoneal-mesh literature. Same keyhole vs. Sugarbaker orientation principles via 3–4 trocars; offers the usual laparoscopic benefits (less pain/morbidity, shorter stay, earlier return to work) when technically feasible — best suited to small/medium defects without a concomitant fascial defect, given the need for 5 cm overlap in all directions.

A meta-analysis (DeAsis, 15 studies 2005–2015, ≥5 patients and ≥1 year follow-up each) found no morbidity difference between techniques (SSI 4%, infected mesh 1.7%, obstruction requiring reoperation 1.7%) but a clear durability difference:

Pooled repairs	n	Technique	Follow-up	Recurrence
11 studies, 2004–2012	231	Laparoscopic keyhole	≥12 months	28%
9 studies, 2005–2013	191	Laparoscopic Sugarbaker	—	10%

This meta-analysis is the primary evidence behind the chapter's key concept that laparoscopic Sugarbaker repair is the procedure of choice for most patients requiring parastomal hernia surgery.

Open retromuscular repair and abdominal wall reconstruction (AWR)

Technically challenging but versatile. A retrorectus dissection alone (posterior rectus sheath dissected from the muscle to the semilunar line bilaterally, stoma re-sited contralaterally when possible before reapproximating the posterior sheaths) may suffice for smaller defects — allows use of cheaper uncoated polypropylene and simultaneous reinforcement of the new stoma site, prior stoma site, and midline. Early pooled results (4 studies, 76 patients): 8% recurrence at 24-month mean follow-up, 4% infection rate, no mesh infections or excisions.

For larger/lateral parastomal defects or a concomitant large midline defect where retrorectus dissection alone can't achieve fascial reapproximation or sufficient overlap, a posterior component separation / transversus abdominis release (TAR) extends the dissection to the lateral preperitoneal plane (division of the transversus abdominis muscle medial to the perforating neurovascular bundles), creating a much larger retromuscular pocket — matured to the psoas muscles laterally, the diaphragm's central tendon cephalad, and the space of Retzius inferiorly. The stoma is typically brought through the resulting mesh in a keyhole/cruciate configuration, though a Sugarbaker-style drape-over-mesh variant has also been described.

Series	n	Technique	Follow-up (mo)	Recurrence	Notes
Raigani	46	TAR/keyhole	13 (mean)	11%	46% SSI rate; only 1 reoperation (mesh erosion)
Beffa	46	Retrorectus ± TAR (TAR in 2/3)	22 (mean)	22%	17% SSI overall, 40% when stoma re-sited
Pauli	44	TAR/Sugarbaker (retromuscular, mesh not fixed to bowel)	10 (mean)	4.5%	No mesh erosion/stoma necrosis reported

The Pauli TAR/Sugarbaker variant looked especially promising at initial multi-surgeon report, but the chapter's own authors' (Cleveland Clinic) experience with the technique was humbling: mesh erosion into bowel in 3/38 patients (8%). They have since modified the technique to avoid fixating mesh adjacent to the stoma and are enrolling a randomized trial comparing open retromuscular keyhole/ cruciate vs. Sugarbaker mesh reinforcement (NCT03972553) — a useful example of a technique looking better in its originators' hands than in independent replication, worth remembering when reading any single-center series in this literature. Stapled adjuncts to retromuscular keyhole mesh (using a 28mm EEA stapler to secure mesh to both rectus sheaths) have also been described: STORRM (12 patients, 17% recurrence at 13-month mean follow-up) and SMART (4/22, 18% recurrence at 21-month median follow-up).

Decision algorithm (Fig. 55.5)

1. Is the patient in extremis, or suboptimized but requiring urgent operation? → Yes: primary closure (emergent maneuver only, high recurrence expected).
2. No → Is the patient optimized (BMI <35–40, HbA1c <7–8%, smoking-free ≥4 weeks)? → No: counsel and reassess in 3 months.
3. Yes → Is the hernia EHS I or III (no concomitant incisional hernia) and <10 cm? → Yes: consider laparoscopic Sugarbaker or open onlay.
4. No (EHS II/III >10cm/IV, or a hostile/high-risk abdomen the surgeon is comfortable managing) → Is the surgeon comfortable with retromuscular repair? → Yes: open retromuscular repair; No: open or laparoscopic intraperitoneal mesh.

Mesh options

Synthetic mesh (uncoated, macroporous, monofilament polypropylene is the most bacterial-burden- resistant option per animal studies) remains the standard for intraperitoneal repairs in optimized, elective, CDC wound class II–III settings — a meaningful shift from earlier damage-control-laparotomy practice where staged synthetic mesh excision was essentially planned. Retromuscular/TAR techniques allow well-vascularized tissue interfaces on both sides of the mesh, minimizing viscera interaction and superficial wound exposure. The largest contaminated-field synthetic mesh series to date (Warren et al. 2020, 402 patients, 30% active smokers, mean 9 cm defects, CDC II 53%/III 42%/IV 6%): 14% SSI, 2.4% mesh excision, 10% recurrence at 21-month median follow-up.

Biologic/biosynthetic mesh has only three prospective (uncontrolled) series:

Study	Mesh	n	Complexity	SSI	Mesh excision	Recurrence
RICH	Porcine dermis collagen	80	Mean 16cm defect, 9% ECF takedown	35%	0%	28% at 2 years
COBRA	Bio-A (long-active resorbable)	104	Mean 9cm defect, CDC III 77%	18%	0%	17% at 2 years
Phasix	Poly-4-hydroxybutyrate (long-active resorbable)	121	Clean, medium defects	9%	0%	9% at 18 months

Overall pattern: biologic/biosynthetic mesh wound morbidity correlates with long-term recurrence, but mesh excision is exceedingly rare with these materials. Synthetic mesh trades a slightly higher mesh excision risk for meaningfully lower long-term recurrence and comparable wound morbidity — favoring synthetic mesh in appropriately optimized, appropriately-contaminated-field patients.

Conclusion (chapter's own summary)

Parastomal hernia repair remains a humbling endeavor with limited evidence-based guidance — every effort should go toward preoperative optimization and familiarity with the full technique armamentarium. Advanced AWR/TAR techniques show promising results and are growing in popularity, but open onlay and both open/laparoscopic intraperitoneal mesh remain reasonable, should-not-be-dismissed options depending on defect characteristics and surgeon comfort.

Open items / gaps

• All content above is textbook-level/secondary, drawn entirely from case series and meta-analyses/pooled-analyses — no randomized trial yet compares PSH repair techniques head to head, a genuine and explicitly acknowledged evidence gap in the field itself rather than just a wiki gap.
• The Pauli TAR/Sugarbaker technique's mesh-erosion discrepancy between its originating multi-surgeon report (4.5% recurrence, no erosion) and the chapter authors' own single-center follow-up (8% bowel erosion) is worth flagging explicitly rather than taking the more favorable published figure at face value — the ongoing RCT (NCT03972553) would be worth checking for results in a future ingest.
• The DeAsis laparoscopic meta-analysis (Sugarbaker vs. keyhole recurrence) and the Warren et al. 2020 contaminated-field synthetic mesh series are the two most load-bearing sources behind this page's key clinical recommendations and would be reasonable independent-ingestion candidates if stoma/hernia-specific research questions arise — not yet added to Research Priorities.md given the wiki's existing backlog, similar to the judgment call made for Ch54.